Tracing layer: semicolon cleanup
Move tracing layer source code file into layers directory
Move tracing tool source code file into tools directory
Move box selection based tools into tools directory
SVG overlay: only process clicks targeted at own view

If one opens another stack of the same project while in tracing mode, it was
possible to create new nodes by clicking in the non-active (!) stack. This could
cause unwanted nodes, possibly even outside of the extent of the active stack,
making the new nodes unreachable. This commit fixes this by making sure a click
event is only processed in an overlay (which triggers the actual node
creation) if its view is the very same the click was targeted at. The event is
not stopped from bubbling up at the moment to make it possible to handle it at
other places. Currently, this triggers the activation of another stack/widget if
there is any.

This closes #419.
Tracing layer: add button to toggle slice controls

Adds a toolbar button to the tracing layer that toggles visibility of
the layer sliders and scale benchmark, complete with terrible icon.
Closes acardona/CATMAID#434.
Stack: add control to toggle slice controls

Adds a button in the lower left of the stack view, similar to the
overview toggle, that toggles visibility of the layer sliders and scale
benchmark. See discussion in acardona/CATMAID#434.
Revert "Tracing layer: add button to toggle slice controls"

This reverts commit 957331916f33c89e01f77a408a252775d0bdc31d.
Overview: fix missing semicolons (minor)

Also remove dead commented code.
Stack: fix slice control toggle pointer CSS (m)
Stack: better stack control toggle icon

Replace the stack control toggle icon with one from @tomka more
consistent with other stack UI and indicating toggle state.
Merge branch 'issues/434-slice-control-toggle'
Extract neuron name service into separate file

Since NeuronNameService is modular and well-decoupled from the rest of
utils.js, extract it to its own file.
Neuron name service: semicolon cleanup (minor)
Doc: make pip update requirement on Ubuntu 12.04 a note
Doc: also install Distribute like NumPy prior to pip-frozen modules

A newer Distribute module is needed to install matplotlib, which is a
dependency specified in the pip-frozen file. Therefore, it has to be
installed before calling "pip install -r pip-frozen", just like NumPy.
Doc: update repository URL and add graphismagick dependency

Thanks to @kotowicz for suggesting theses changes. This commit changes
the documentation so that HTTPS is used for the CATMAID repository URL
(instead of GIT protocol). Also graphicsmagick is added as a dependency
to make it possible to run the suggested "gm convert -list format"
command).

Closes #726.
Doc: use current year in copyright notice
Doc: update contributors
Doc: refer to configuration.py when showing an example of admin URL