Also, retain storage qualifiers in type_decl, in particular
also for function pointers.  This allows to get rid of this
very early hack in decl()
    type.t |= (btype.t & VT_STATIC); /* Retain "static". */
which was to fix the case of
    int main() { static int (*foo)(); ...

Also:
- missing __declspec(dllimport) is an error now
- except if the symbol is "_imp__symbol"
- demonstrate export/import of data in the dll example (while
  'extern' isn't strictly required with dllimport anymore)
- new function 'patch_storage()' replaces 'weaken_symbol()'
  and 'apply_visibility()'
- new function 'update_storage()' applies storage attributes
  to Elf symbols.
- put_extern_sym/2 accepts new pseudo section SECTION_COMMON
- add -Wl,-export-all-symbols as alias for -rdynamic
- add -Wl,-subsystem=windows for mingw compatibility
- redefinition of 'sym' error for initialized global data

- from win32/include/winapi: various .h

  The winapi header set cannot be complete no matter what.  So
  lets have just the minimal set necessary to compile the examples.

- remove CMake support (hard to keep up to date)
- some other files

Also, drop useless changes in win32/lib/(win)crt1.c

    And a new console demo program: taxi and passengers simulator

A non declared function leads to a seriuos problems. And while
gcc don't turn this warning on lets tcc do it. This warning
can be turned off by -Wno-implicit-function-declaration option.
And autor must explicitly do this if program must be compiled
with this warning off.