Adding oauth2.0 token refresh

Merge pull request #13 from mojaloop/feature/MBXSDK-9

Add OAuth2.0 periodic token refresh functionality

Bug fixes for http response headers

Hotfix/response header validation (#12)

* Commet response header validation for content-type

* updated version number

* Updated code to disable content-type validation

* updated throwOrjson method

* Added unit test for common file

* Added more tests

* replaced tape with ava

v7.4.0

Bump release version to reflect mojaloop versioning scheme

v0.0.39

First release tag after move from modusbox repo

v0.0.39-snapshot

test circle ci npm publish