Fix MALDateTools

- added support for formats to formatDateString():
  - yyyy-MM-dd
  - yyyy-MM-dd'T'HH:mmZ
  - yyyy-MM-dd'T'HHZ
- removed crashlytics logging from formatDateString as it is not useful
  there
Merge pull request #301 from d-sko/maldatetools_fix

Fix for MALDateTools