Feature release

Added

• New "pause" button on debugger that sends SIGINT to remote process
• New "interactiveTerminal" debugger option to run remote programs in
  interactive terminal instead of output pane
• New setting for device connection timeout

Fixed

• Fix debugger restart button not working
• Fix numbers not allowed in ev3devBrowser.env variable names

Changed

• SSH shell no longer requires native executable on Windows
• Device connection timeout increased to 30 seconds