Printrun 2.0.0rc6

Pre-release for testing purposes.

New Features

• Change the default background color to the theme one (#931)
• Add setting for graph background color (#791)
• Hide second extruder from graph if not present (#791)
• Support for disabling Mate screensaver service (#979)
• Armenian translation (#1042)
• Don't print the M117 status msg to the console (#1081)
• Packages installable by pip are available on PyPI (#921)

Fixed Bugs

• Don't ask for exit confirmation on the console when asking in GUI (b48fe7b)
• Preset for temperatures does not affect Selection on the main screen (#676)
• Several Python 3 related followups, mostly in run_gcode_script
• Issue connecting to a remote port (#1027)
• Run "Final command" from settings when print is finished (#1014)
• Fix a crash in wx at startup due to locale settings (#1015)
• Only apply PARITY_ODD workaround where it's actually needed (#1017)
• Do not attempt to read extra device name patterns on windows (#1040)
• Several Linux packaging fixes
• Removed error-causing wxPython horizontal alignment flags (#1052)
• Rewrite deprecated Serial functions (#1017), pySerial >= 3 is now needed
• 3D Viewer color options don't update (#1054)
• Settings change callbacks not called (#1063 and others)