Develop python package struct

[mexanick]

Description

Restructured reg_interface package, separated gem-dependent parts and provided build tools

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Motivation and Context

Now the package can be built and installed without most parts of the gem dependencies. CI tools has been added too.

How Has This Been Tested?

Tested with Travis CI and on the eagle64

Screenshots (if appropriate):

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.