fix(parser): abort expanding recurring events when end is reached

[tripodsan]

fixes #34

• the fix extends the parser by allowing to specify the desired start end end range.
• recurring events are expanded until:
  1. completed, or
  2. when reaching the specified end range
  3. or 10 times, when no end range is specified

[movd]

could this please be merged?

[antosan]

Thank you @tripodsan for your PR. While reviewing we noticed that the implementation of the parser regarding the expansion was a little buggy. We expanded all the events from the start date and had to filter them again afterwards. We refactored this buggy behaviour in the parser and took into consideration your suggestions as well in #48.