Fix service preemption by putting it into foreground.

Note that NOTIFICATION_ID is changed, because startForeground doesn't work with 0.
Add support for an API key
Merge pull request #157 from denevell/preferences_screen

Added preferences screen for nickname.
Merge pull request #160 from dougt/api_key

Add support for an API key
Merge pull request #154 from pepyakin/master

Fix service preemption by putting it into foreground.
Merge remote-tracking branch 'upstream/master'