publishers: campaign withdraw UI, inclusion proof checks

[Ivshti]

There should be a UI In the dApp that allows publishers to see all campaigns they've earned from: expired/exhausted(past) AND active

to guarantee publisher security, inclusion proofs must be checked on the client side (in the dapp)

in other words, the adex-protocol-eth js libs should be used to check whether the latest signed state (as collected by the validators, directly) really guarantees you the revenue that it appears to

[Ivshti]

duplicates with #46

since both contain useful information, I'm not gonna close them for now

[Ivshti]

no longer relevant cause of the relayer