I was unsure how to update the QwtPlotPrintFilter code, so I just commented it out with a FIXME.

Also deleted invalid line drawing options.

Fix HIL link reconnect issues due to missing threading flag usage, warn user about missing config and take him to config view if necessary

espeak: provide string length with 0 character, fixes problems with qgc reading out strange values/chars at the end of the sentence

This way the delete happens on the right thread.