* fix some deadlocks found by evil lock manager (tm)
* fix duplicate lock
* fix indentation
* ensure proper lock dependencies
* fix lock acquisition
* removed useless comment
* do not lock twice
* create either a V8 transaction context or a standalone transaction context, depending on if we are called from within V8 or not
* AQL micro optimizations
* use explicit constructor
* only use V8DealerFeature's ConditionLocker for acquiring a free V8 context
entering and exiting the selected context is then done later on without having to hold the ConditionLocker
* remove some recursive locks
* Disable custom deadlock detection when Thread Sanitizer is enabled
* Changing ifdef's
* grr
* broke gcc
* Using atomic for ApplicationServer::_server
* fix premature unlock
* add some asserts
* honor collection locking in cluster
* yet one more lock fix
* removed assertion
* some more bugfixes
* Fixing assert
(cherry picked from commit 1155df173bfb67303077fbe04ee8d909517bfd21)
* do not use V8 variant of AQL functions in early optimization stage when a C++ variant is available
* additionally, simplify AQL function definitions and aliases
* warn when more than 90% of max mappings are in use
* added C++ variant of replication catchup
* added `--log.role` option
* updated CHANGELOG
* removed non-existing scheduler.threads option from config
* removed useless __FILE__, __LINE__ invocations
* updated CHANGELOG
* allow a priority V8 context
* remove TRI_CORE_MEM_ZONE
* try to fix Windows errors & warnings
* cleanup
* removed memory zones altogether
* exclude system collections from collection tests