[GH #890] Generate MANIFEST.generate, remove MANIFEST_configure.generated

Some files are still missing.
add_to_generated($filename, $section, $dir) is called from the Makefile
shell via tools/build/addgenerated.pl, and from $conf directly.

Improve docs Makefile
[GH #890] Add missing MANIFEST.generated files, cleanup

Also move MAN_1 to docs, and improved clean targets

Comparison from old manual MANIFEST.generated.orig to generated
MANIFEST.generated:
Added all previous MANIFEST_configure.generated entries, esp. Makefiles.
Moved include/parrot/pbcversion.h from devel to main. (used by config.h)
Removed invalid and outdated entries.
Added previously missing entries.

+compilers/tge/tgc.pbc                            [main]
+config_lib.pir                                   [devel]
+docs/binaries/ops2c.1                            [main]man
+docs/binaries/parrot-nqp.1                       [main]man
+docs/binaries/parrot-prove.1                     [main]man
+docs/binaries/parrot.1                           [main]man
+docs/binaries/parrot_config.1                    [main]man
+docs/binaries/parrot_nci_thunk_gen.1             [main]man
+docs/binaries/parrotbug.1                        [main]man
+docs/binaries/pbc_to_exe.1                       [main]man
+docs/binaries/plumage.1                          [main]man
+docs/binaries/winxed.1                           [main]man
+docs/ops/index.pod                               [doc]
+docs/packfile-c.pod                              [doc]
+foo_group.h                                      [devel]include
+include/parrot/pbcversion.h                      [main]include
+install_config.o                                 [main]lib
+runtime/parrot/dynext/foo_group.bundle           [library]
+runtime/parrot/dynext/pccmethod_test.bundle      [library]
+runtime/parrot/dynext/rotest.bundle              [library]
+runtime/parrot/dynext/subproxy.bundle            [library]
+runtime/parrot/include/cloneflags.pasm           [main]
+runtime/parrot/include/packfile_annotation_key_type.pasm [main]
+runtime/parrot/include/packfile_segments.pasm    [main]
+runtime/parrot/library/NCI/Utils.pbc             [main]
+runtime/parrot/library/OpenGL/Math.pbc           [main]
+runtime/parrot/library/PCT/Dumper.pbc            [main]
+runtime/parrot/library/ProfTest.pbc              [main]
+runtime/parrot/library/ProfTest/Matcher.pbc      [main]
+runtime/parrot/library/ProfTest/Matcher.pir      [main]
+runtime/parrot/library/ProfTest/NQPProfile.pbc   [main]
+runtime/parrot/library/ProfTest/NQPProfile.pir   [main]
+runtime/parrot/library/ProfTest/PIRProfile.pbc   [library]
+runtime/parrot/library/ProfTest/PIRProfile.pir   [main]
+runtime/parrot/library/ProfTest/Want.pbc         [main]
+runtime/parrot/library/ProfTest/Want.pir         [main]
+runtime/parrot/library/String/Utils.pbc          [main]
+runtime/parrot/library/URI/Escape.pbc            [main]
+runtime/parrot/library/YAML/Dumper/Base.pbc      [main]
+runtime/parrot/library/YAML/Dumper/Default.pbc   [main]
+runtime/parrot/library/postgres.pbc              [main]
+runtime/parrot/library/yaml_dumper.pbc           [main]
+src/core_pmcs.c                                  []
+src/dynpmc/pmc_dynlexpad.h                       [devel]include
+src/dynpmc/pmc_file.h                            [devel]include
+src/dynpmc/pmc_foo.h                             [devel]include
+src/dynpmc/pmc_foo2.h                            [devel]include
+src/dynpmc/pmc_gziphandle.h                      [devel]include
+src/dynpmc/pmc_osdummy.h                         [devel]include
+src/dynpmc/pmc_pccmethod_test.h                  [devel]include
+src/dynpmc/pmc_rational.h                        [devel]include
+src/dynpmc/pmc_rotest.h                          [devel]include
+src/dynpmc/pmc_select.h                          [devel]include
+src/dynpmc/pmc_subproxy.h                        [devel]include
+src/glut_callbacks.c                             [devel]src
+src/glut_nci_thunks.nci                          [main]
+src/string/private_cstring.h                     []

-docs/ops/debug.pod                               [doc]
-docs/ops/dotgnu.pod                              [doc]
-docs/ops/obscure.pod                             [doc]
-docs/ops/pic.pod                                 [doc]
-docs/ops/stack.pod                               [doc]
-include/parrot/exec_dep.h                        [main]include
-include/parrot/pbcversion.h                      [devel]include
-include/pmc/pmc_codestring.h                     [devel]include
-include/pmc/pmc_context.h                        [devel]include
-include/pmc/pmc_packfilefixupentry.h             [devel]include
-include/pmc/pmc_packfilefixuptable.h             [devel]include
-include/pmc/pmc_select.h                         [devel]include
-runtime/parrot/include/iotypes.pasm              [main]
-runtime/parrot/include/parrot_version.pir        [main]
-runtime/parrot/include/signal.pasm               [main]
-runtime/parrot/include/vtable_methods.pasm       [main]
-runtime/parrot/library/Data/Replace.pbc          [main]
-runtime/parrot/library/HTTP/Daemon.pbc           [main]
-runtime/parrot/library/NCI/call_toolkit_init.pbc [main]
-runtime/parrot/library/PGE/Hs.pbc                [main]
-runtime/parrot/library/Parrot/Capture_PIR.pbc    [main]
-runtime/parrot/library/Parrot/HLLCompiler.pbc    [main]
-runtime/parrot/library/Protoobject.pbc           [main]
-runtime/parrot/library/YAML/Dumper/Base.pmc      [main]
-runtime/parrot/library/YAML/Dumper/Default.pmc   [main]
-src/call_list.txt                                [devel]src
-src/glut_callbacks.c                             []
-src/install_config.obj                           [main]lib
-src/jit_emit.h                                   []
-src/nci.c                                        []
-src/pmc/codestring.dump                          [devel]src
-src/pmc/packfilefixupentry.dump                  [devel]src
-src/pmc/packfilefixuptable.dump                  [devel]src
-src/pmc/select.dump                              [devel]src
-src/string_private_cstring.h                     []
-tools/build/dynpmc.pl                            []
-tools/dev/testnumbers                            [devel]
-tools/dev/testnumbers.bat                        [devel]