Fixing PerformanceTest: table_exists condition, move getMemoryAmount function to file. Add more debug helpers (#905)

* Fix missing includes

* ComplexKeyCacheDictionary: Move includes to .cpp

* Fixing PerformanceTest: table_exists condition, move getMemoryAmount function to file. Add more debug helpers

* Multiplatform memory size getter

* Requested changes

* Requested changes

* Requested changes

* fix

* Requested changes