add some features for more complete 'long' support

tcc.h:
- use LONG_SIZE=4/8 instead of TCC_LONG_ARE_64_BIT
tccgen.c:
- add ptrdiff_type, update size_type
- support shift and ?: operations
- support long enum types
- display 'long' from type_to_str
- nwchar_t is unsigned short on windows
- unrelated: use memcpy in init_putv for long doubles to avoid
  random bytes in the image (if tcc was compiled by gcc) for
  diff purposes.
tccpp.c:
- make parse_number return correct types
- improve multi-character-constants 'XX' 'abcd'
Changelog:
- update

with more things I remember having done :)

Forgot about it.  It allows to compile several
sources (and other .o's) to one single .o file;

    tcc -r -o all.o f1.c f2.c f3.S o4.o ...

Also:
- option -fold-struct-init-code removed, no effect anymore
- (tcc_)set_environment() moved to tcc.c
- win32/lib/(win)crt1 minor fix & add dependency
- debug line output for asm (tcc -c -g xxx.S) enabled
- configure/Makefiles: x86-64 -> x86_64 changes
- README: cleanup

usage:
    tcc -ar [rcsv] lib files...
    tcc -impdef lib.dll [-v] [-o lib.def]

also:
- support more files with -c: tcc -c f1.c f2.c ...
- fix a bug which caused tcc f1.c f2.S to produce no asm
- allow tcc -ar @listfile too
- change prototype: _void_ tcc_set_options(...)
- apply -Wl,-whole-archive when a librariy is given
  as libxxx.a also (not just for -lxxx)

- lib/Makefile: add (win)crt1_w.o

- crt1.c/_runtmain: return to tcc & only use for UNICODE
  (because it might be not 100% reliable with for example
  wildcards (tcc *.c -run ...)

- tccrun.c/tccpe.c: load -run startup_code only if called
  from tcc_run(). Otherwise main may not be defined.  See
  libtcc_test.c

- tests2/Makefile: pass extra options in FLAGS to allow
  overriding TCC

Also:
- tccpe.c: support weak attribute.  (I first tried to solve
  the problem above by using it but then didn't)

- tcc-doc.texi: commandline option info update
- Changelog/TODO: update
- tests/tcctest.py: removed
- tests/Makefile: weaktest fixed
- tests/tests2: some files renamed and/or converted to unix LF
- configure/Makefile: --enable-static option (no dll on win32)
- win32/build-tcc.bat: msvc support
- win32/tcc-win32.txt: build info update
- win32/vs2015/: VS solution removed
- win32/include/tcc/tcc_libm.h: #include statement fixed
- tcc.c: -include <file> option help info
- .gitignore: cleanup

 * Documentation is now in "docs".
 * Source code is now in "src".
 * Misc. fixes here and there so that everything still works.

I think I got everything in this commit, but I only tested this
on Linux (Make) and Windows (CMake), so I might've messed
something up on other platforms...

perl -i -pe 'use Text::Iconv;
$c1 = Text::Iconv->new("utf-8", "utf-8");
$c2 = Text::Iconv->new("iso-8859-1", "utf-8");
if (!$c1->convert($_)) { $_ = $c2->convert($_); }' \
`find * -type f`