Fix code block indent in ordered list
Merge pull request #21 from remiprev/fix/markdown-whitespace-in-stellartxt

Fix code block indent in ordered list
Update Coinex's url.
update docs
add cold/hot wallet section
adjust readme
Merge pull request #22 from bekkibolthouse/master

Adds Contributing.md to docs repo and updates broken links in multi-currency doc
Fixes broken link to stellar.txt

The casing “stellar” caused the link from readme.md to break.  Changed
s to S.