rule_engine.c: ib_rule_id_match() now only has a single behavior.

A rule id is considered to match the rule id of an ib_rule_t if:
  1) That ib_rule_t's id or full_id match.
  2) Any rule preceeding the ib_rule_t in a rule chain's id or full_id
  match.
  3) Any rule following the ib_rule_t in a rule chain's id or full_id
  match.

Compared with the previous behavior, this is as if both arguments were
true but recursion is not used, so no excessive looping will take place.
rule_engine.c: ib_rule_tag_match() now matches if any rule in a rule chain contains the given tag.
rule_engine.c: The Rule Engine now enables and disables rules according to a single list. Enable/disable directives are applied in configuration order.
rule_engine.c: Adding error reporting for when Rule{Enable,Disable} id:x fails to find the rule.
rule_engine.c, rules.c: Implement enabling and disabling rules by id and tag prefixes, RNS-1271.
smart_stringencoders.cpp: Implement smart_{url,html,classic}_decode() transformations, RNS-1137.
smart_stringencoder.cpp: Include const in reinterpret_cast.
smart_stringencoders.cpp: Code review adjustments. Moved some decoders. Fixed decoding ordering. RNS-1137
release.h.in: Bumping ABI number.
abi_compatibility.hpp: Bumping IronBee++ ABI number.
Fixed clipp proxy mode response and request creation.
lua: Update docs and error messages surrounding LuaStackMin/LuaStackMax settings. RNS-1267
init_collection.c, configure.ac, **/Makefile.am: Remove conditional support for Yajl. The JSON library is a hard requirement for IronBee. RNS-1288
predicate/standard_string.cpp: If a subvalue submitted to StringReplaceRx() is null, do nothing and return a null value, RNS-1265.
clipp will exit with a non-zero value if a consumer throws an exception.
utf8.cpp: Adding UTF8 module implmementation, library, and unit tests. RNS-1303
CHANGES.adoc: New UTF-8 module.
tc_utf8.rb: Do not use assert_true. Prefer assert().
modules/tests/Makefile.am: Adding tc_smart_stringencoders.rb to EXTRA_DIST.
libs/Makefile.am, modules/Makefile.am: Prefix include list with local directory. Include local directory (utf8_v2.3.4) in EXTRA_DIST.