add YARA for ClamAV header file.
include calling YARA rule parser during ClamAV database load.
fixes make dist.
Fix build on windows (yara currently excluded).
add yacc/lex wrapper.
Revert "add yacc/lex wrapper."

This reverts commit 4e524a57700bea5ee9cc80f2e059a4f71c6342a0.
add yacc/lex wrapper.
add YARA grammer and tokenizer files (gutted).
YARA work in progress.
YARA work in progress: add parser skeleton, add string and rule queuing.
pull ascii, nocase, and wide keywords from YARA rule strings.
Generate a very basic LDB entry from the strings loaded from a yara rule
Merge remote-tracking branch 'origin/smorgan/clamy' into swebb/clamyara

Conflicts:
	libclamav/readdb.c
Initialize the roots before trying to load the generated ldb sig
Whitespace cleanup
More whitespace cleanup
Initialize nstrings
Support hex strings
Phase 1 of yara hex string parsing: gather number of substrings and lengths of those substrings
Yara hex string parsing, phase 2: Stuff the strings.