Improved Model.enable_adjust_position()

Improved Model.enable_adjust_position() and update_plot() such that
componets plotted also update as parameters change, and not just the
total model plot. Also, added an optional parameter to not plot labels
in enable_adjust_position()
Merge remote-tracking branch 'vidars/live-component-plot-update' into 0.7.1
BUG_FIX: Signal._assign_subclass was not changing the subclass when setting signal_origin due to a typo.
Automatic style corrections courtesy of autopep8.
Add test.
Automatic style corrections courtesy of autopep8.
Merge pull request #273 from francisco-dlp/BUG_FIX_assign_subclass

Bug fix assign subclass
Added suspend/resume of Model.update_plot()

If changing several parameters at once, the plot would currently update
once for each change. This commit adds a suspend_update() /
resume_update() function pair to temporariliy disable updating until all
changes have been completed.
DataAxis bugfix + value2index takes ndarray

Fixed a bug in DataAxis._get_name() when the axes_manager was not set.
Also, DataAxis.value2index() now accepts ndarrays as input.
Fixed DraggablePatch picking

Previously, there was no mechanism for setting a DraggablePatch.picked
to False when it was no longer picked.
DataAxis.value2index was not using the rounding argument when value was a numpy array.
Add tests.
Automatic style corrections courtesy of autopep8.
Update value2index docstring
Merge pull request #278 from vidartf/draggable-patch_picking

Fixed DraggablePatch picking
Merge pull request #1 from francisco-dlp/data-axis_bugfix

Data axis bugfix
Merge pull request #276 from vidartf/data-axis_bugfix

DataAxis bugfix + value2index takes ndarray
IPython.frontend is deprecated

Newer versions of IPython give the following warning:
UserWarning: The top-level frontend package has been deprecated. All its
subpackages have been moved to the top IPython level. warn("The
top-level frontend package has been deprecated. "

Fix as according to Google.
Disconnect/reconnect parameters on suspend/resume

Disconnect parameters to update_plot on suspend_update, reconnects on
resume_update (if _get_auto_update_plot() returns True). Also changes
_get_auto_update_plot() to check for suspension, as several internal
functions rely on it. Because of this, it is important that
resume_update decrements the counter before it checks
_get_auto_update_plot.
Docstring updates Model.suspend/resume_update