Error hitting "Enter" on Filters

[benloh]

Seems to happen after Login:

1. Start graph without logging in
2. Go to log in
3. Enter a login token
4. IMPORTANT: Hit "ENTER" to login.
5. Go to Highlight/Filter
6. Select Label "contains"
7. Type something in the field
8. Hit ENTER
9. The page reloads.

The error doesn't seem to happen if you don't login using "ENTER" (e.g. if you use the URL)

[benloh]

The Node Filters, Edge Filters, Node Filter Transparency, and Edge Filter Transparency are implemented as 4 different forms. Each would accept a "ENTER" as a submit, triggering the page reload.

6e491d5 should fix that by explicitly catching and suppressing the submission.