Problem in the cfg file fixed & packages updated

Merge remote-tracking branch 'origin/master' into dev

File extension changed from .DYALOG to .APLC

Bug fix: referencing '\''zipFilename'\'' caused Value Error

:Include APLTreeUtils fixed

Meaningful msg in case 7z.exe cannot be found

The z7 setup adds the path to the EXE to the system vars "PATH", so normally it should just work, but sometimes it does not, and thren a meaninful error msg was missing.

Documentation and test cases improved

7zip's "List" mehtod is buggy, but at least that is documented now

Bug fix: VALUE ERROR on `counter`

Occurred only when a zip action failed, for example on a slippery network

Initial commit