Student<->Tutor chat implemented
Handshake session start working
Dark theme
Set tutor as unavailable if they accept a student
Remove unused TutorsProfile activity, some cleanup
Rename some activity layouts, small fixes to User class
Merge remote-tracking branch 'origin/JoyDev3' into StevenDev

Conflicts:
	UberTutorAndroid/app/src/main/AndroidManifest.xml
	UberTutorAndroid/app/src/main/java/ee461l/ubertutorandroid/StudentHandshakeActivity.java
	UberTutorAndroid/app/src/main/java/ee461l/ubertutorandroid/ViewProfileActivity.java
	UberTutorAndroid/app/src/main/res/values/strings.xml
Merge fix
Merged with master