Refs #8560. Corrected RB functionality

Lots of changes:

* The RB search is no longer triggered by textRB's editingFinished signal. It's now linked to textRB's returnPressed and the new buttonSearch's clicked. So this will now only search when enter is pressed in the text box or the search button is clicked.
* A search won't be attempted if the RB box is empty
* transfer() and the RB search will display an error message in a messagebox if something goes wrong.
* The main window now has a status bar, used for showing search status.
* The RB search no longer uses cycles, and will search every journal from the beggining of time to the present day
* The RB search is much faster (it's practically instant) due to using summary.txt (located alongside the xml journals) instead of the xml journals. It's guessed that the speed gain has come from only opening one file over a network rather than many, the xml module might have also been slightly to blame.
* The RB search no longer adds cycle directories to the managed user directories - this is a side effect of using the summary.txt as that doesn't include the cycle so the fucntion can't add the cycle directory.

A decision is being made on which  direction to take in terms of seraching, as both xml and txt methods are in the code and it's a case of changing a single function call to switch them. txt is instant, but doesn't add cycles to the managed directories, while xml takes about 40 seconds but adds cycle directories to the managed directories
Refs #* develop. Merge branch 'feature/8560_Refl_gui_RB_functionality' into develop