updates & cleanups (tcc-doc/Changelog/TODO ...)

- 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

tcc.c

@@ -109,6 +109,7 @@ static void help(void)
            "  -E          preprocess only\n"
            "  -P[1]       no / alternative #line output with -E\n"
            "  -dD -dM     output #define directives with -E\n"
+           "  -include file  include file above each input file\n"
            "Linker options:\n"
            "  -Ldir       add library path 'dir'\n"
            "  -llib       link with dynamic or static library 'lib'\n"