pmt response modeled as normal dist. Slow
poisson stat of electron multiplication added
conversion to current pulse
Merge branch 'develop' into pmt-dev

Conflicts:
	src/dacsim.py
	src/pmt.py
	src/scintillator.py
Merge branch 'pmt-dev' into develop
dacsim.py modified to work properly with new pmt function
dacsim.py modified to work properly with new pmt function
pmt documentation added
example input documented as code
Merge branch 'pmt-dev' into develop

Conflicts:
	src/dacsim.py
cable documented
digitize documented and sampling frequency added
pmt modified to give amplitude independent of the sampling time dt
poisson noise due to electron multiplication now treated properly
Merge branch 'develop' into pmt-dev

Conflicts:
	src/dacsim.py
Merge branch 'pmt-dev' into develop
Normalization of pmt response added
Merge branch 'pmt-dev' into develop
transit time added to pmt
Merge branch 'pmt-dev' into develop