Provide regression test case for bsdcat on empty compressed files
Allow empty files (after filters) in bsdcat command.

This changeset fixes an issue with empty compressed files, i.e.
files that after inflating are of size 0:  bsdcat would report
unrecognized archive format for those because the raw reader is
unable to handle files of zero length.
Merge pull request #87 from hroptatyr/fix/cat-empty-file

Allow empty files (after filters) in bsdcat command.
Add lz4 test for bsdcat.
 - add test utility function canLz4()
 - fix test_write_filter_lz4 to use canLz4()
Add additional tests for lz4 compression in front-end applications.
Fix issue 375: failure to read some larger .7z archives
Increase a maxinum entry limitation up to 100000000 from 1000000.
fixed hang in UUEncode filter
Style fix.
Fix build failure of xxhash on Ubuntu.
Add support for Traditional PKWARE decryption to zip reader.
Add support for extracting WinZIp AES encryption.
Simply traditioal encryption api.
Fix comment. Do not use one line comment statement '//'
because some compiler does not recognize it.
Fix decryption in streamable mode.
Add support for traditional PKWARE encryption.
Make sure zip reader skips whole its contens.
Rename archive_hmac.h archive_hmac_private.h
Move cryptographic functions into archive_cryptor.c.
I will rename archive_crypto.c to archive_digest.c.
Add support for WinZip AES encryption.
Skip a test if the platform does not have cryptographic functionarity.