Merge pull request #42 from IPA-Lets-Study-Together/dev

Duplicate code removal
Merge pull request #45 from IPA-Lets-Study-Together/issue_44

Issue #44 implementation
Merge pull request #46 from IPA-Lets-Study-Together/dev

text/css header
Merge pull request #47 from IPA-Lets-Study-Together/dev

Implemented block instance configuration form
Added line-height:normal for some basic elements and changed form label size to match user style
Merge pull request #48 from hitteshahuja/dev

Added line-height:normal for some basic elements and changed form label size to match user style
Developers documentation added, Defaults.php was missing