Simplify search, put back support for namespaces and trash

[RogerHaase]

Remove undocumented option to enter search query in url:

Example URL: http://127.0.0.1:8080/+search/OtherTextItems?q=moin

use documented form in query field instead

>othertextitems moin

Put back namespace and trash support.

Fix info message when using AND OR NOT: "Common words omitted from query: or, and, not "

Eliminate use of confusing Whoosh Filters when searching by content types:

18 items found, 4 more items filtered by content types.