intial commit
[CHORE] clean up callbacks, polling logig
[CHORE] fix polling logic
[FEATURE] combine discount, convert and get exchange to one module
[CHORE] moved to convert
[CHORE]  clean up clutter, fixed incoming payment model
[CHORE] improve polling logic
[CHORE] clean entry point calls
[CHORE] update endpoint to block chain
[FEATURE] blockchain call test
[FEATURE] unit test convert
[FEATURE] exchange rate call unit test
[FEATURE] hot wallet test
[FEATURE]  email module test
[FEATURE] transaction flow test
Merge branch 'master' of github.com:ripple/ripple-gateway-btc