* convert MainActivity to Kotlin
* migrate to MaterialDrawer 8
* fix drawer styles
* revert removing BezelImageView and material_drawer_header override
* fix tests
* add lost comment back to material_drawer_header.xml
* add tools:parentTag to material_drawer_header.xml
* use when instead of if in MainActivity
* fix statusbar color over the drawer
* cleanup drawer item creation
* tint secondary drawer items as well
* remove unnecessary ids
* fix header text color in the light theme
* improve header text contrast
