Major bugfixes related to noise floor computations

Previously, functions that returned a noise floor would have the bootstrapped
mean estimate of the noise floor too low due to the way the trials were
selected. This has been corrected; see moddepth_analysis_example_results.csv in
the analysis folder for sample output from the current version.
Merge remote-tracking branch 'upstream/master'
various formatting fixes, updated examples
documentation update; ensured that all functions computing PLV can also do ITC
if params['itc'] is set
Merge pull request #7 from lennyvarghese/master

noise floor fix