Fix html preheader for html welcome email.

Some email clients showed a weird preview containing the style elements
of the header. This is now fixed by a long title, which has a starting copy of the
page content. This seems to be the most portable solution.
CURRIKI-6545 Add Filter Defaults to File Check

- Added default filter for resources without a status
- Added default filter for dates from Jan. 2014 to today
Add CRS/Reviews as page to the repository.
CURRIKI-6546 Add Filter Defaults to CRS

Add a default filter to "Mathematics"