Merge pull request #6 from kyledrake/master

Force JSON for post body
0.1.2 (+ok @ryanxcharles)
Update Travis for Ruby 2x, pull jruby
added plugin version header
Merge pull request #7 from unChaz/master

added plugin version header
Update README.md

Trying again..
Merge pull request #9 from unChaz/patch-3

Update README.md
remove hard-coded version string from req header

Use the gem version constant instead of the string existing in
multiple places. This will prevent confusion in case the client
version is bumped but the request header gets missed. This could lead
to potential confusion if Bitpay ever needs to debug version of Ruby
client used to access the API.
Merge pull request #10 from nmarley/plugin-info-header

remove hard-coded version string from req header