Improve template caching

[silvester747]

Mako generates python code for the files it uses as its templates. All files are used at least twice, and the internal templates likely much more frequently. Improve the caching of the templates.

• [x] Cache internal templates in the build directory
• [x] Separate adoc and internal template cache
• [x] Command line parameters for cache settings
• [x] Disable file system checks