Do not set default labels

[jgosmann]

Motivation and context:
Given the nengo/nengo-gui#1002 has been merged, not setting any default labels will give more informative labels in the Nengo GUI. This also converts all networks to classes to be more consistent.

Interactions with other PRs:
none

How has this been tested?
existing tests

How long should this take to review?

• Average (neither quick nor lengthy)

Most lines did just change in indentation (due to init being nested in the class) and have net renamed to self.

Types of changes:

• Breaking change (fix or feature that causes existing functionality to change)

Checklist:

• I have read the CONTRIBUTING.rst document.
• I have updated the documentation accordingly.
• I have included a changelog entry.
• [n/a] I have added tests to cover my changes.
• I have run the test suite locally and all tests passed.

[jgosmann]

It would be great to get a review on this. @tbekolay @tcstewar @Seanny123

[Seanny123]

@jgosmann to make sure I understand this PR, to review, I should install the master branch of Nengo GUI and this branch of Nengo SPA. Then, I should see the better labels discussed in this PR and in the linked Nengo GUI PR?

[jgosmann]

Exactly. I made some example screenshots:

Without this PR, if no explicit label is set, all State modules (for example) are just labeled "State":

With this PR, if no explicit label is set, the modules are labeled based on the assigned variable:

If the module is not assigned to a global variable, the label defaults to the class name (e.g. State).

Independent of this PR, explicitly setting the label will display that label:

There is also somewhat graceful degradation with older Nengo GUI versions than the current master. If no explicit label is set, but the module is not assigned to a global variable, it will be labeled "networks[i]" (where i is some integer).

[Seanny123]

Works as expected on Windows 10.