Increment to version 4.4

Increment version.

See merge request !587

Feature/substepping

Introduction of a working version of a substepping version of the Incompressible Navier Stokes solver. 


See merge request !553

Issue warning and ignore empty XML tags

This MR modifies the session reader logic to ignore empty XML tags which would otherwise replace non-empty tags. This prevents, for example, the empty CONDITIONS section generated by NekMesh from displacing the user-provided conditions if the user condition file is supplied before the mesh file on the command-line.

@ssherw: This has been tested locally and everything passed. Just running through buildbot now.

See merge request !581

Tester updates for testing tutorials

The MR adds an option to the Tester code to allow the executable specified in the .tst file to be overridden on the command-line. This is to allow the use of executables which lie elsewhere in the build tree, not just in the directory containing the Tests directory.

It also fixes support for input files to be located in a different directory to the test file itself. It would previously fail if the list of dependent files included a relative path to a file in a different directory.

Finally, there are also a couple of tweaks to the submodule so git ignores it when things have changed.

See merge request !580

Add OS X packaging for binaries

This MR adds packaging for OS X.

See merge request !544

Updated Set_Rhs_Magnitude to use a predefined weight. Also introduced a switch not to use the weight when running the Multi-Level static Condensation

updated the Set_Rhs_Magnitude method to only use a maixmum of 1000 counter steps in its weighting. The use of a member variable instead of a static int has also changed how the magnitude and therefore tolerance is evalauting requiring a change in the values in the .tst file

tags which replace non-empty tags.

Optimisations for DG code

This MR adds optimisations for DG code. This is achieved by preprocessing the mesh topology to identify similar interpolation methods that can be blocked together and generating longer scatter and gather mappings. These are then used in the GetFwdBwdTrace method as well as AddTraceIntegral type methods. This has been introduced in 2D and 3D but not 1D. 

See merge request !555

Feature/field convert interp block

This branch introduces two features to Fieldconvert and one to StdReigons.

In FieldConvert the module InterpPoints can now take a box argument which extracts a block of points from the field file in a box region defined by xmin,xmax,ymin,ymax,zmin,zmax. This routine and the plane of points were also extended to be able to run in parallel and then the files could be concatenated together to produced a working .dat file

In addition the module PointDataToFld was introduced which takes a set of interpolated points from another source of data (such as RANS) at the quadrature distribution of a .xml file and projects these points onto a .fld file.  This can use either the default equispaced collapsed points to interpolate or better use the Gauss quadrature distribution of points by specifying an option noequispaced. This is better since it is possible to get singular matrices with the equispaced points on deformed elements (Since the quadrature is not sufficiently accurate).

To get around the issue of singular matrices in PointDataToFld a preliminary implementation has also been introduced into StdRegions called EquiSpacedToCoeff which takes an equispaced set of points and projects/interpolates them directly to the coefficient space. This is possible of a uniform order is adopted. This method has not yet been used in FieldConvert  and so a regression test has been setup to test the method in Demos/StdRegions. 

See merge request !561