User experience improvements:
- Add welcome activity with a short introduction
- Add version info and GitHub link to info activity
- Do not require two long clicks for first time start
- Warn user about missing configured hosts files
- Improve various user-facing strings
Bugfixes:
- Fix downloading of hosts files on Lollipop
- Support host files containing only one column
- Correctly lower-case host names for comparisons
Legal:
- Include copyright, COPYING, and LICENSE.Apache-2.0 in the
generated APK