[FEATURE] make maxLoops in seed.get_key optional

default to 1 or the index of the requested account +1
[FIX] vault client: URI decode attestation token
Merge pull request #182 from shekenahglory/fix/attestation

[FIX] vault client: URI decode attestation token
Merge pull request #179 from geertweening/develop

[FEATURE] make maxLoops in seed.get_key() optional