Style corrections.
Add . Also improve the Scree plot section of the User Guide by incluiding a figure.
Merge pull request #177 from francisco-dlp/ENH_get_explained_variation

Enh get explained variation
Add missing figure from previous commit
Merge branch 'master' of https://github.com/hyperspy/hyperspy
Automatic style corrections, courtesy of autopep8
Merge pull request #181 from francisco-dlp/autopep8

Automatic style corrections, courtesy of autopep8
Merge branch 'master' into DOC_improved_EDS

Conflicts:
	hyperspy/_signals/eds.py
	hyperspy/tests/signal/test_eds_tem.py