[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
[DOC] update release notes
[TASK] bump version to 0.9.0-rc1
[FEATURE] add flag to show or hide interest in to_human/to_json

The show_interest flag will default to true for interest bearing currencies and false for currencies without interest
Merge pull request #184 from geertweening/show_interest_flag

[FEATURE] add flag to show or hide interest in to_human/to_json
[FIX] run test by _mocha to capture coverage
[DOC] update release notes
[TASK] bump version to 0.9.0-rc2
[FIX] binformat: added missing TransactionResult options
Merge pull request #185 from shekenahglory/fix/serialize

[FIX] binformat: added missing TransactionResult options
[DOC] update release notes
[TASK] bump version to 0.9.0-rc3
[FIX] Amount.to_human() precision slicing instead of rounding
Merge pull request #187 from ripple/amount_precision

[FIX] Amount.to_human() precision slicing instead of rounding
[FIX] fraction_part is a string
[DOC] update release notes
[TASK] bump version to 0.9.0-rc4