make mocks test folder a python package

otherwise coverage get's confused and reports 0% coverage
Removed httpretty tests

These tests aren't maintainable anymore and don't add any value
over mock tests we already had. Also, we decided that it's more
important to have a more comprehensive live tests suite that is run
via travis.
add mock tests for id site
remove httpretty as dep from tox.ini
small fix to Resource base class
add more tests for resource base class
add tests for account module
fix py3 compatibility issues
Merge pull request #78 from denibertovic/remove_httprettys

Remove httprettys