Multiple changes from Donatas

[donce71]

gui.py
1 New button and input field for Fine camera max value adjustment
2 Target Ra/Dec input format changed. Now user just needs to paste from hh:mm:ss
hardware.py
1 Drivers for PhotonFocus added
2 flip_y method: typo with flip_X
system.py
1 get alingment list from csv file. (Option to reuse old alignment file, to skip auto-alingment procedure).
2 read ex_command.csv file for offset correction
tracking.py
1 log track data added: P_term, I_term
2 External offset file (ex_command,csv) check and update

[sylvesterkaczmarek]

This imports harvesters unconditionally at module load, but the project requirements do not include it and existing ptgrey users do not need PhotonFocus support. Importing pypogs.hardware will therefore fail for existing installations without the optional SDK. Please make the import lazy/optional inside the phfocus path (or declare an explicit optional extra).