Mavenized project
added german translation
many improvements

- fixed coding style (applied standard android/java style)
- improved string concatenation to avoid unnecessary allocations in loo (hint: avoid + operator in loop)
- applied fix mentioned in issue #2
added a dismiss listener

- this is very useful if you want to change the activity once the dialog has been closed (e.g. in a splash screen activity)
fixed copy&paste error
Merge pull request #3 from hameno/dev

Mavenized project and other improvements