Design compile time api hs_compile_lit() and hs_compile_lit_multi() to handle pure literal pattern sets. Corresponding option --literal-on is added for hyperscan testing suites. Extended parameters and part of flags are not supported for this api.
We now use NGHolder for all graph information, while other expression properties (report, flag information, etc) go in new class ExpressionInfo.
Adds new "edit_distance" extparam
