Allow experiment.fromFile() if filename parsing fails
Fixing conflicts
Add rolloff vs height fitting
Merge branch 'feature-refolding'

Incorporating fixes to processing images to .fret from refolding
data, and loading those experiments.
ADD calibration IPython notebook
Merge branch 'master' into feature-refolding

Adding IPython notebook folder and calibration notebook
FEATURE fitting with fec module

Moving some functionality out of experiment.py and into
fec module for fitting WLC and rips of pulling data.

Trying to take a more functional approach, passing data around
and using module function to operate on it, leaving things
like experiment.Pulling to shuttle data around.

Should that object also have things like rips added to it?
For example,

    mol.rips = fec.Rips(...) ??

This would keep all the results in one place, while keeping
the Pulling object clean of excessive methods.

TODO: remove duplication from curvefit.py and experiment.py

	modified:   browser.py
	modified:   datatypes.py
	modified:   experiment.py
	new file:   fec.py
	new file:   shell.py