Elasticipy

The main changes of this release are:

- The Voigt, Reuss and Hill averages are now computed from the stiffness/compliance orientation attribute
- plot() has been renamed plot3D()

**Full Changelog**: https://github.com/DorianDepriester/Elasticipy/compare/1.1.0...2.0.0

Full documentation available on ReadTheDoc

Fix bug with wrong relative path to modules

Change tree managing, so that all modules are submodules of Elasticipy

First release