Rename catarse_fee configuration to platform_fee

Despite Neighborly being a fork of Catarse, there is no need to
associate the source with with Catarse.
Update neighborly-balanced-bankaccount gem
Update neighborly-balanced gem
Merge pull request #81 from neighborly/im-rename-catarse-fee-config

Rename catarse_fee configuration to platform_fee
Merge branch 'master' into ach-balanced