Add option to plot individual components with model.plot

Several changes:
- Rename the old component.__call__ to __tempcall__ (Need to find better
  name)
- Change component.__call__ to behave similarly to model.__call__ and
  spectrum.__call__
- Add component._component2plot adapted from model._model2plot
- Add plot_components to model.plot (default False)
Make SpectrumLine.line_properties a property
Remove SpectrumLine.set_line_properties_helper. Now the line_properties property takes care of the type keyword
Add automatic color cycling when adding SpectrumLine to SpectrumFigure
Add _disable_plot_components and _enable_plot_components to Model
Set SpectrumLine.autoscale to False by default and enable it only for the spectrum line
Merge branch 'master' into plot_components
Merge branch 'plot_components' of github.com:hyperspy/hyperspy into plot_components
Normalize EOL
Merge branch 'master' into plot_components

Conflicts:
	hyperspy/component.py
	hyperspy/drawing/mpl_hse.py
	hyperspy/model.py
make enable/disable plot_componets public
Add plot_components documentation