FLIP

[PhylomatX]

• Added methods for implementing a FLIP simulation for liquids.
• Added demo of FLIP simulation
• Added masked extrapolation method for tensors and for CenteredGrid / StaggeredGrid
• Added small tests for extrapolation method
• Added position shift methods to geometries
• Added runge-kutta advection scheme with velocity-dependent extrapolation
• Rewrote distribute_points method
• Changed duplicate_handling in PointCloud sampling method

[PhylomatX]

• Applied all refactorings
• Merged / Removed some of the methods
• Implemented new merge method for PointClouds with & operator