Tests: Use environment variables to get the API keys
Core: Update README.md
Merge pull request #1 from peregrinogris/fix-readme

Fix readme and use environmental variables to get the api keys
Tests: Complete tests for all the resources.
Merge pull request #2 from peregrinogris/fix-tests

Tests: Complete tests for all the resources.
Merge pull request #3 from Mango/develop

Merge develop into master