Documentation update. We don't use explicite @brief doxygen statements.
Variable name change to match convention.
Lua RuleExt instances do not fail transactions if they fail to execute.
When a Lua module exits with an error or non IB_OK report it and return IB_OK.

This avoids aborting the transaction in process.
Core collection manager: Fix a bug which caused the variable name matching to be too restrictive.
Managed collections: Logging cleanups
various: Refactor ib_operator_execute() to ib_operator_inst_execute() for consistence with other operator instance routines.
IronBee++/operator: Add Operator and ConstOperator.
CHANGES.md: Add new IronBee++ operators.