Add coordinator dashboard

[0xmad]

As a coordinator I'd like to run cli commands using maci-rpgf website.

• Add coordinator dashboard page
• Show deployed polls
• Show number of signups for each poll and status
• Add ability to deploy new poll #65
• Add ability to finalize the poll #66
• Add ability to deploy maci instance #67

[kittybest]

Also, it's necessary to display which stage is currently in progress: accepting applications / voting / voting ended, need to perform tally / display result, also links to related pages (e.g. reviewing application submissions, etc.)

--> so something need to be discussed: are we going to run several rounds in the same maci-rpgf application? since I think the current logic is only running one round (so only 1 poll would be deployed)
--> running multiple rounds means we need to rerun the process of accepting application submission?