Adds a list of Frequencies which you can click on to tune to it.

The list is read from (on Linux) : ~/.config/gqrx/frequency-list/radio.csv

The File List looks like this:

```
 98500000, Bayern3     , WFM       , 400000
 99000000, Oe3         , WFM       , 122000
105700000, Bayern 5    , WFM       ,
```

Modulation and Bandwidth are not yet used.
Converted frequency-table to a dock window.
Auto select row in frequency-table.
Support more Freq-Tables and selecting via Combobox.
small changes to frequency-list.
Merge branch 'master' into bookmarks

Conflicts:
	gqrx.pro
New bookmark system. Bookmarks are now shown in plotter.
Merge branch 'master' into bookmarks

Conflicts:
	applications/gqrx/mainwindow.cpp
	qtgui/plotter.h
Merge branch 'master' into bookmarks
Refactoring and improvements
Merge branch 'master' into bookmarks

Conflicts:
	applications/gqrx/mainwindow.cpp
	applications/gqrx/mainwindow.h
	applications/gqrx/mainwindow.ui
	gqrx.pro
	icons.qrc
Fix in saving bookmarks.csv file
Bookmarks tag color is now correctly saved
Fix various minor issues in the bookmarks patch.

List files in gqrx.pro in alphatical order.
Move all bookmarks sources to qtgui to avoid including headers from
applications/gqrx.
Add complete file headers.
Rename sample bookmarks file.
Change bookmark field separator to ';'
Updated readme.
Update bookmarks include.
When clicking on Bookmark, also set Modulation and Bandwidth.
Add a right-click menu to the Bookmarks Table with a "Delete" entry.
Fix errormessage "Ignoring Line" when loading bookmarks.csv.