Contributions not validated server side

[dafky2000]

Exploited on Amusement Park's start up plan. Simply modified the signed message to have 100 contributions instead of undefined and submited. Server accepted as valid vote!

[cazala]

Thanks for reporting @dafky2000. This should be fixed by #90, we are testing on staging before releasing to prod.

[abarmat]

This has been fixed by PR #90 and release https://github.com/decentraland/agora/releases/tag/1.0.2