* add ability to remove tabs from tabs view interface (#3147)
* an "X" on each tab is visible in edit mode
* replaced custom removeDialog with openmct.overlays.dialog
* Minor mods to markup and CSS
- Changed tab from button to div to allow a cleaner approach to the
nested close button;
- Changed close "icon-x" span to a button and added `c-click-icon` style
tag;
- Tweaked class naming to simplify and align with a more functional/
descriptive approach;
* use ES6 arrow func to avoid self=this
Co-authored-by: Deep Tailor <deep.j.tailor@nasa.gov>
Co-authored-by: charlesh88 <charlesh88@gmail.com>
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