DASH v4.0.0 Alpha Test 2.0.0

This is the second alpha release for DASH v4.0.0. The major update is the addition of modules for state vector design.
Documentation for state vectors is at: https://jonking93.github.io/DASH/Tutorials/stateVector/welcome

Other updates:

1. Adjusted gridfiles to use relative paths by default.
2. Added additional error assertions and structure preallocation to the dash utility class.