Introduce chimera hybrid engine of Hyperscan and PCRE, to fully support
PCRE syntax as well as to take advantage of the high performance nature of
Hyperscan.
New API feature: logical combinations (AND, OR and NOT) of patterns in a
given pattern set.
Windows porting: hsbench, hscheck, hscollider and hsdump tools now available
on Windows 8 or newer.
Improve undirected graph implementation to avoid graph copy and reduce
compile time.
Bugfix for issue #86: enable hscollider for installed PCRE package.
