apply patches from patchdir
build/deps fixup

- dont try to copy my files around.
- set SHELL to bash, otherwise sourcing env might fail
Merge branch 'build_system' into python_sage_build
config.py
Makefiles update

- numerical backends makefile cleanup
- pycheck simplified
- some 5.12 beta4 updates
forgotten config.py template
Merge branch 'python_sage_build' into sagelib
Merge branch 'sagelib' into toplevel-WIP3

Conflicts:
	build/deps
CXX fix (needs work)
get rid of transition files

- src/bin/install-sh
- src/bin/sage-dist-install
- src/bin/sage-dist-make
toplevel register ncurses foreign package
sagelib: spkg, draft

this will be required by a proper toplevel build system
sage-bin: cleanup env

- adapt env
- remove sage-arch-env
- remove SAGE_ROOT hacks
- remove ECLDIR (ecl takes care of it)
sage-bin adapt various scripts

- sage-build
- sage-spkg.in
- sage-sdist
sage-bin: sage.in

- config files to @SAGE_ETC@
- cleanup
- PIPESTATUS_CMD
sage-bin: sage-build
toplevel transition: cleanup bin/sage-env

runtime paths will be taken care of by sagelib/spkg-install
sagenb: postponing; no idea how to workaround #14840
python-sage more explicit import/include paths (unneeded?)

intended to work with -I<parent_directory_of_'sage'>
python-sage: simplify include directives, lrcalc, fplll?

- lrcalc will not work without -I/path/to/include/lrcalc anyway
- fplll will not work without -I/path/to/include/fplll anyway