* Removes TNT Unicode controls, which are no longer required. All VCL controls now have native Unicode support.
* Remove Delphi 11 packages, otherwise we would either need to keep TNT or break Unicode
* PngComponents update from Uwe Raabe on http://cc.embarcadero.com/Item/26127
* Adjust auto build process
* Since Delphi 2009, Strings are now UnicodeStrings, not AnsiStrings any longer. Fix a bunch of compiler errors which came along with this change.
TODO: Project should compile but give tons of compiler warnings.
* Move const.inc and compilers.inc back to main source directory
* Move remaining few lines of code from heidicomp.pas to helpers.pas
* Remove components/compilerdetection and components/heidisql
* Remove remainders of EDBImage component, unused since Aug 08.
