Add PTI incentives

[jellegerbrandy]

Assuming $0.10 as our "price parameter" for 1 gb of filesharing, we can make things easier by assigning 0.10 PTI to the same amount of work (1PTI = $1). It's a bit tougher on decimals (closer to the scale of what will be the real metrics). We can also make it a bit more rewarding:

+1 PTI - Confirm email.
-0.50 PTI - Post a video.
+0.50 PTI - Have more than 100 views on an uploaded video
+1 PTI - Have more than 1.000 views on an uploaded video
+5 PTI - Have more than 10.000 views on an uploaded video
+3 PTI - Have >70% positive ratings with >100 ratings.
+0.50 PTI - Suggested a tag that ended up being suggested by more 10 users (which makes it be displayed along the 2 tags that go along the video), at any point before the 10th user.
+0.20 PTI - Flagged a video that ended up being removed by us.
+0.20 PTI - Someone visits a video through the custom link you generated.
+-0.01 PTI - For each 100 Mb of debt / credit in filesharing.

Implementation plan:

• write an onchain contract (or contracts) that has a budget for assigning this rewards
• the contract is controlled by an account held by our meteor server
• a user does an action --> pings our server --> server calls contract --> contract awards pti
• the reason what we pass trhough our server (instead of just callign the contract diretly from the client) is that we need to validate the pre-conditions (and doing this isn solidity is only partially possible, and much more work)
• the rewards contract has 50K Paratii budget.