Fixes
* cease explicit propagation of unhandled key combinations to parents
* fixes 310 , 311, 312
* fix can extraction in case of CAN OBD2 messages and ignore_invalid_signals=True
* avoid urllib error in tests
* handle VLSD channels with channel_type Unsigned motorola or unsigned intel
Changes
* persisting last opened file path in QSettings
* connecting 'Ctrl + O' shortcut to Open File
* sync regions in the sub-plots