Using Content provider and DBhelper

problem: cant retrieve the data in mainactivity from provider and
dbhelper classes
Revert "Revert "new fragment 'about'""

This reverts commit 40dfdb9f1351f6b15a6d25591f5bdcdd371e237f.
Merge remote-tracking branch 'origin/master'

Conflicts:
	LectureRecorder/.idea/misc.xml
	LectureRecorder/app/src/main/res/layout/fragment_about.xml