Add instrument paper preprint.
Update ubuntu install docs.
Update windows install docs.
Add CCD-ROUT header key for readout time.
Replace TIMER_HIGHRES_TIMING -> TIMER_TRIGGER_MODE.
Change shutter preference GUI.
Add an option for disabling the first exposure time alignment. Fixes #18.

Requires karaka commit 300833c8 or later.
Allow bias frames to be acquired using internal triggering. Fixes #24.
Enable bias frames for pvcam.
Adjust / store exposure time when switching trigger mode.
Update windows docs with ssh installation.
Enable bias mode for the ProEM.
Fix incorrect gain string query. Fixes #19.
Save CCD-EMGN fits header key for recording EM gain. Fixes #14.
Save CCD-SCUT fits header key for recording ProEM exposure shortcut.
Save CCD-SHFT fits header key for recording vertical shift times.
Save TRG-ALGN fits header key for recording trigger alignment.
Move CCD-TIME header next to other time keys.
Fix UTC-LOCK recording T independent of actual GPS lock status.
Merge pull request #1 from pchote/master

update