jupyter-matlab-proxy 0.2.0 release

Features:

1. Dynamic display port selection. Previously, the integration relied on display :1 being available; with these changes the next free display is selected and used.
2. Fix 409 error on login page. Occurred when users toggled between Online Login and Server licensing screens.
3. Unit Tests added
4. Internal security patches
5. Infrastructure for proper error messages for Add-On explorer browser window. (Needs more work)