remove ext/zip dependency entirely, write better native zip support

remove ext/zip dependency entirely, write better native zip support
re-organize, create util.c, move entry_info/archive_data/entry_data access methods to this file
refactor entry->fp, now this is abstracted with phar_get_efp() and phar_seek_efp(), fixes all weird dependency issues
permanently solve the "millions of file pointers" issue for read access.  All compressed files are read into a single
temporary stream, and their constraints are controlled by the entry->fp abstraction

Improvements in this zip implementation over ext/zip:
 * full read/write support for bzip2 compressed files
 * much more efficient access for accessing only a few files within large zip files, as crc/header validation is
   done just-in-time
 * full stream support for opendir/rename/rmdir/mkdir as well as all of the other stream funcs
 * full support for setting file perms via Phar::chmod(), stored as zip-standard extra field
 * no problem with large zips and many open file pointers

# TODO: add big-endian system support for tar/zip file format headers, otherwise the implementation is complete
# TODO: test on windows and fix any windows-specific issues
# TODO: verify zips created work with unzip/winzip/windows explorer and so on