Plan view to display activities (#3413)

* (WIP) Adds Plan view and visualization of activities on different rows

* Updates to show activities in the right rows

* Improve algorithm to get activityRow for next activity

* When activities have names that are longer than their width, show the name outside the activity rectangle

* Remove Activity component as we don't need it right now

* Use canvas to draw activities instead of svg for performance

* Retain SVG version if needed

* Include text when calculating overlap

* Fix padding, text positioning

* Add colors for activities

* Fixed bug - Rectangle was shrinking as time passed
Draw using SVG

* Adds performance activities

* [WIP] Refactoring code to be more readable

* Fix issues with activity layout

* Adds draft for groups

* Adds x-offset for groups

* Draw a "now" marker for the canvas

* Fix formatting for the timeline

* Adds now line for the timeline

* Add ability to upload a plan json file.

* Add tests for the Plan view

* Fix issue with File Type checking
add resizing for timeline view plans

* Refactor code to be more readable

* Fix tests that are failing on circleCI

* Fix icon for timeline view

index.html

@@ -48,6 +48,7 @@
         openmct.install(openmct.plugins.MyItems());
         openmct.install(openmct.plugins.Generator());
         openmct.install(openmct.plugins.ExampleImagery());
+        openmct.install(openmct.plugins.Timeline());
         openmct.install(openmct.plugins.UTCTimeSystem());
         openmct.install(openmct.plugins.AutoflowView({
             type: "telemetry.panel"