DOC: further improvements to the model selection exercise
ENH/FIX add a lobpcg solver to spectral embedding

This makes the solver a bit better behaved on some problems
MISC: decrease verbosity by default
FIX: numerical stability in spectral

This enables me to unskip a skipped test, hurray!
MISC: addressing @satra's comments
ENH: make sure that spectral EVD is solve once
MISC: @agramfort's comments
PEP8
doc: added reference to lobpcg and note about small number of nodes
BUG: fix test error
Fix indentation
ENH removed ``remove_zeros`` parameter.
BUG: make precision_recall invariant by scaling probs
BUG: fix setuptools feature

for instance 'python setup.py develop'
Discretization method for spectral clustering added along with tolerence setting to loosen eigendecomposition constraints
Documentation and small bugs fixed and code cleaned up
Small comments/constants added
Fix typos
Added more info in documentation
Small aesthetic fixes to discretization