Core collection manager: Fix a bug which caused the variable name matching to be too restrictive.
Added "LogHandler" directive (which just logs a notice) for 0.6 compatibility
Log event: Handle empty transactions
TxDump: Handle empty transactions
IncludeIfExists: Reduce log message level to debug if errno is ENOENT
ironbee++/operator: Move instance methods and register_with to ConstOperator as the C API's only need const ib_operator_t*.
ironbee++/operator: Move operator_cleanup() impl function from hpp to cpp.
Setvar: Handle setting of existing fields to a value of the same type, even in collections
Merge branch '0.7.x'
Revert "Added "LogHandler" directive (which just logs a notice) for 0.6 compatibility",
not required for 0.8.x+

This reverts commit 586592288bf1270ad0d7b3715476445333b2bca8.
Fixed some doxygen errors
modhtp: General clean-up pass.  Added asserts() and doxygen headers where
they were missing.
core_operators.c, ironbee++/operator.hpp: Casting style.
ironbee++/operator.hpp: Include order.
managed_collection.c, pcre.c: Indentation cleanup.
core_actions.c, engine.h: Strip whitespace.
operator, modhtp: Spell check.
IronBee++/ModuleBootstrap: Module delegates are now constructed on initialization rather than load.
IronBee++/Module: Add with_name() to acquire a module by name.
IronBee++/c_trampoline: Documentation fix.