fixes occasional NPE

Merge branch 'develop'

fixes release jar

Re-introduces possibility to set Configuration from within Style

Version 1.8

- Improves support for custom views
- Smoothing out animations for multiple line Croutons
- Cleans up Style
  - Configuration is now available for non-UI information
    - Style only holds UI-relevant information
    - Introduces DURATION_SHORT and DURATION_LONG constants

updates README for 1.7 release

Merge branch '1.6'

updates README