R5:3170bc15592e

Use more css and phorge standard elements for application view

Summary:
This diff streamlines the application view. This includes:

- using the newPage method of the PhabricatorController
- using the application crumb standard class for rendering of crumbs
- using 📊 as application glyph
- using css and flex for sizing of the drawio app iframe (circumvents magic css numbers)
- implementing some phorge coding standards

Test Plan: Creating and editing diagrams (and older versions) look at the new…