ripple/ripple-lib — pull request #213 by geertweening (2014-11-25 18:23:12+00:00)
Title: [FEATURE] improve memo support

- add MemoFormat property for memo
- MemoFormat and MemoType must be valid ASCII
- Memo content is converted on the serialization level
- add parsed_* version of Memo content if the parser understand the format
- support `text` and `json` MemoFormat