* new Settings activity
* Settings: display/change user name, password, preemptive auth.
* Settings: display/change sync. interval for contacts and calendars
* requires permission GET_ACCOUNTS to list accounts in Settings
* requires permission READ_SYNC_SETTINGS to display current sync intervals
* remove obsolete files from res/
* update copyright notices
* version bump to 0.7
* SSLConnectionSocketFactory is now SNI-capable, so there's no need
to manage SNI in DAVdroid
* keep secure protocol/cipher suite definitions
* use a patched jar until https://issues.apache.org/jira/browse/HTTPCLIENT-1591 is fixed
* moved all dependencies to gradle instead of shipping .jar files in the app/lib directory
* switched to official Android port of HttpClient instead of httpclientandroidlib
* new .gitignore and project files