Before, the search was a single value.
Now it is splited in chuncks when separated by spaces.
Except if they are enclosed by single quotes or double quotes.
For some reasons, the unit tests are working for both single and double quotes but the
search box isn't. It is working only with single quotes.
We need to investigate the reason of this behavior.
See #823
There were multiple calls made to the cleaning method that were unnecessary since it is useful only on the last call.
It allows to simplify code by returning values ealier.
I figured that the code for the search could be extracted from the context to have separation of concern.
It supports multiple keywords. It suports also multiple tag keywords.
