add logSettingsController
add download logfile button
move getEntries to LogSettingsController
move set log level to logsettingscontroller.php
add warning if logfile is bigger than 100MB
add unit test for set log level
fix typecasting, add new line at EoF
show log and logfile download only if log_type is set to owncloud
add unit test for getFilenameForDownload
First step of a somewhat testable user management. - I know, the JSON returns are in an ugly format but the JS expects it that way. So let's keep it that way until we have time to fix the JS in the future.