run-time: Split run-time compilation targets

* sources/lib/run-time/Makefile.in: Split run-time compilation targets
  so that they can be compiled with different compile flags, in
  preparation for adding the LLVM run-time.
dylan-compiler: Add a -back-end command line option

* sources/environment/console/command-line.dylan
  (%back-end): New slot in <basic-main-command>
  (do-execute-command on <basic-main-command>): Set the
   compiler-back-end property when the %back-end is set.

* sources/environment/console/compiler-command-line.dylan
  (back-end): New command-line keyword.

* sources/environment/console/environment-command-line.dylan
  (back-end): New command-line keyword.
[conversion] Fix warning.

Handle the un-expected #f return value by erroring.
[dood] Add a note explaining the warning.
Merge pull request #831 from waywardmonkeys/fix-conversion-warning

[conversion] Fix warning by minor code restructuring.
Bug 5880: Fix iteration over non-<integer> ranges

* sources/dylan/range.dylan
  (range-next-state, range-previous-state): Declare return value
   as <number> to avoid breakage when type checks are not disabled
   for the dylan library.
[dfmc-c-ffi] Fix typo.
[c-ffi,tests] Clean up some whitespace.
[c-ffi,tests] Comment out struct-passing tests.

These tests use code that passes a struct by value. That code was
already commented out, but these tests that also called that same
code were not.

Disable for now.
[io] Specialize stream-lock on <stream>.

Previously, stream-lock was specialized on <basic-stream> which is
where the lock is actually defined in the code. However, lock-stream
and unlock-stream are specialized on <stream> and the default
implementation calls stream-lock (which isn't available for all
<stream> instances).

This also makes the test for this pass in the io-test-suite.
[pprint,tests] Update specification to match code.

The pprint-newline, pprint-tab and pprint-indent methods specify
that they take a restricted set of symbols, not just <symbol>,
so update the specification tests to reflect that.
[docs,c-ffi] Fix warnings.

This fixes a few "Title underline too short." warnings in the C-FFI
docs that were introduced with the <C-size-t> changes.
[docs,common-extensions] Link to Format docs.
Merge pull request #840 from waywardmonkeys/pprint-specification

[pprint,tests] Update specification to match code.
dylan: Fix return type of a subtype? method

* sources/dylan/type.dylan
  (subtype? on <limited-collection-type> and <class>): Fix return
   value declaration to permit #t.
Bug 7458: Fix primitive-c-*-at{,-setter}

* sources/dfmc/llvm-back-end/llvm-primitives-ffi.dylan
  (raw-accessor-primitive-definer): Properly use both offset and byte-offset
   in the computation of the pointer address.
Bug 7458: Fix dependencies on dead code

Generate values for referenced temporaries generated by dead
code (following loops, etc.)

* sources/dfmc/llvm-back-end/llvm-emit-computation.dylan
  (emit-dead-assignment on <temporary>,
   emit-dead-assignment on <multiple-value-temporary>): New methods
   to assign a dummy value to the generated temporary.
  (emit-computations): Assign dummy values using emit-dead-assignment
   when the emitted computation does not fall within a valid basic
   block.
Merge pull request #839 from waywardmonkeys/stream-lock-specification

[io] Specialize stream-lock on <stream>.
[dpkg] removed rpath hack from .deb generation script
[dpkg] Debian packages now include man pages.