pre. 0.2-Release: slightly improved item-rendering + logout.

Features:
- after an item was tagged or voted, just the result-item is re-rendered
  (resulting in a kind of "static" result-set-view)
- rendering "you're logged out now" when logout was successfull

Fixes:
- updated README

Code-Changes:
- changed MathJax Delimiter back to "$$"
  to be removed completely from the sight of user
- removed some debug statements

Pending:
- current layout currently does explicitly not support IE9, IE10 and Opera

Documentation:
https://www.eduzen.tu-berlin.de/software-komponenten (German)
https://www.eduzen.tu-berlin.de/zur-notizen-webanwendung (German / Get User Account)