Added post roll to timelapse

You can now define an amount of seconds that should be added to the rendered timelapse (so, since the current fps setting is 25 frames per seconds, 25 * the configured amount of post roll seconds images will need to be captured).

Timed timelapses add this to the actual run time of the timelapse capturing process (so if you configure 1s post roll, a timed timelapse will run 25s longer than the print)

Z-triggered timelapses just create one last capture from the webcam and use this image again and again (so 25 times for a post roll of 1s).

Implements #384
Fix for saved timelapse configs vs. new post roll setting

See #384
Do not try to send bed temp on API if not available
Virtual printer now supports "repetier style" target temperature reporting
Fixed a regex matcher
Fixed M110 and sd status reporting on virtual printer
Added configurable timeout settings for temperature and sd status query, made communication timeout reset everytime a non-empty line is received from the printer
Do not overwrite possibly existing target temp if only a single hotend is present

See #360
Operate on current transformation matrix when zooming

Closes #398
Merge pull request #2 from foosel/devel

Devel