For Term app , name changed with altname added as Topic

**Modification**
* While displaying Term as app name now its displaying altname added as Topic
* Also added the defination on landing  page of Term app i.e Topic app now 
* Currently when user clicks on Term app the url which is to be followed based on name "term" will be displayed ,which wil replace with altname later on.
* Altname added in ```create_term_app.py``` script while creating term app using script.

**What is to check**
* check all the link names on Topic app in ATLAS group which are currenlty replaced with altnames as "Topic"