added favicon
added bootstrap theme
added site titles
fancy login and registration
Revert "added bootstrap theme"

This reverts commit 27f27da06602a61ffceaee528cda73bda1ff0e9e.
remove dark background color from panel
fix height of progress bar. text was not fully visible
add favicon also to the rest of the frontend
Merge pull request #36 from songster-project/feature/pretty_login_v2

Feature/pretty login v2
fix current song
hide previous song if preview is diesabled
get right event
Merge pull request #38 from songster-project/feature/hide_previous_songsv2

Feature/hide previous songsv2
anonymous username set as guid
disabled login for anonymous user via formular
checking against multiple votes at post route in backend
and deny it