Test h-type convergence with a projection demo

Issue/feature addressed

Previously no test for h-type convergence.

Proposed solution

Add a demo and test of h-type convergence of a continuous Galerkin projection.

Implementation

Demos/MultiRegions/Project.cpp projects a 1D sine function into the eModified_A basis, repeats that several times with different element sizes then calculates the convergence rate.

Tests

Five tests added, for continuous projection with 4,5,6 and 7 modes, and local projection with 6 modes.

Suggested reviewers

@dmoxey

Notes

Checklist

• Functions and classes, or changes to them, are documented.
• User guide/documentation is updated.
• Changelog is updated.
• Suitable tests added for new functionality.
• Contributed code is correctly formatted. (See the contributing guidelines).
• License added to any new files.
• No extraneous files have been added (e.g. compiler output or test data files).