Move all highlighters to a separate directory

[pyscripter]

Currently there are 111 pas files in the Source directory. More than half are highlighters. I suggest that we move all highlighters to a subdirectory of Source to make source less cluttered.

Downsides:

• All packages would need to be updated
• An extra path would need to be added to the Delphi search path.

What do you think?

[pyscripter]

Implemented in #172