This commit contains the entire btcjson repository along with several
changes needed to move all of the files into the btcjson directory in
order to prepare it for merging. This does NOT update btcd or any of the
other packages to use the new location as that will be done separately.
- All import paths in the old btcjson test files have been changed to the
new location
- The coveralls badge has been removed since it unfortunately doesn't
support coverage of sub-packages
This is ongoing work toward #214.
Define errors (previously done in btcwallet and btcd's rpcserver) in
one place so they can just be called by name rather than generated in
code using btcjson.
Closes#5
