Update MainLogic.java

Changed main logic
temp=new List<String>() (in My_Biblio_class.java, line 31) ist
auskommentiert und temp ist auf null gesetzt.
Merge branch 'master' of https://github.com/soroa/flashcards.git
not much new...
Study Function works now
For some reason deleteWord crashes when started
Still need to test Search and Add Word. 
Problem = I can't delete libraries. Every time the application is
started a new TestLibrary is created. 
-> Check delete_library();
import library is still not working on my phone.