2.0: Cannot redeem !

[orenyodfat]

see #1975 (review)

• maybe only for none contributionReward proposal. (maybe not)

[roienatan]

There are two unrelated problems to solve this issue:

• Analytics fails.Need to check that contributionRewards defined.
• There is no redemption function in arc.js for SchemeFactory and SchemeRegistrar.

This issue depends on this daostack/arc.js#516