Release Name: 0.6.0

Notes:
This release adds some features that are required for continuous use of the app, most notably the possibility to delete old data.

Also a horizontal (time axis) zoom with some predefined levels has been added.

Quality-wise, it should work for most people. I'm calling it beta quality.


Changes:
Changes for 0.6.0:
* Time axis zoom selection
* Old data can now be deleted through GUI
* Fixing a graphing accuracy problem on start of charging
* Not plotting graph for time when daemon wasn't running
* Displaying at most of 30 days of data
  (unlimited data display was causing slowness and crashes)