UI: pulsate canvas lists until user hovers over one

First of a few usability/interaction improvments intended
to improving the user's experience and making functionality
more aparent
UI dev.js: s/custom_operations/this.custom_operations
UI: fix 'loading resource' status indicator

Previously was not being rendered since resource loader did
not have handle to status_indicator at the point it was used.

Also due to recent gfx updates Star entities have one less
asynchronous component (a good thing) which is reflected here
UI: refactor Loader module (no functional changes)
UI: add comment
UI: add splash dialog (work in progress)