Get HEMTT working

[Freddo3000]

This pull request will:

• Make this project buildable using HEMTT build and HEMTT build --release
• Correct a few case-sensitive paths
• Add an include directory recognized by HEMTT
• Convert UI macros to not use EXEC/EVAL, as HEMTT doesn't support it. Old versions of files are included
• Update gitignore HEMTT recommendations
• Update HEMTT template.

Notes:

HEMTT config is more or less copied from CBA, with some minor tweaks.

Files macros.inc and macroExecs.inc differ from those included in A3 in order to get it to build. Old versions of files are included for reference.

[Freddo3000]

On hold until https://feedback.bistudio.com/T79801 is resolved