Fix for inserted codes while registering of extensions, many rewrites/cleanups:

Fix for inserted codes while registering of extensions, many rewrites/cleanups:
- Fix for extension registration, codes like {OPEN_CONFIG} and such are no
  longer compiled in while the extension gots registered. This come handy for
  e.g. our POINTS replacement.
- More usage of countSumTotalData() which should reduce the number of SQL
  queries in the whole script
- Replaced a lot double-quotes with single-quotes
- Other minor cleanups