[Mne_analysis] mne report command

[Mainak Jas]

Dear all,

We're converging on the `mne report` command that I was working for the
Google Summer of Code this year.

The idea is to run the `mne report` command as below:

$ mne report --path MNE-sample-data/ --subjects-dir
MNE-sample-data/subjects --subject sample

providing it the data directory whose report must be created. It will
generate a report as a single html file which can be easily shared with
collaborators via email or dropbox. A link to the report generated from
the MNE sample dataset is provided below:

https://dl.dropboxusercontent.com/u/3915954/report.html

The motivation is that it can be used to generate a quick
summary/statistics of the results and do a quality check with minimal
scripting. Typically, this is something one might want to run one day
after data collection.

We also provide a python interface for more advanced users who want to
embed their own custom plots in the report.

Any feedback towards improving this is most appreciated. Thanks!

Best regards,
Mainak