Added multiple-streams-in-parallel version of hitfinder
Merge branch 'testing' of github.com:antonbarty/cheetah into testing
Added more traps for thread lockup - need to add a timeout wherever waiting for all threads to exit
Fiducial not being read meant files were overwriting each other, causing HDF5 library errors.  Added a fix using frame number as the fiducial if not read from XTC.  Could happen to the timestamp as well.
Save full powder pattern along with gaincal and darkcal (useful to have the additional statistics, for example to identify bad pixels).
Speedup: Assemble 2D images only when really needed. 1) Sum powder patterns in raw data only; assemble once right before writing to file; 2) Assemble image only for frames that will be saved.
hitfinder: Updates to process multiple streams in parallel (-c keyword); unfortunately -s was already taken!
Minor changes