ENH: Added new zoneBlended scheme

Multi-faceZone based blending differencing scheme.

Schemes are set in dictionary format according to:

divSchemes
{
    .
    .
    div(phi,U)      Gauss zoneBlended
    {
        default         defaultScheme;
        faceZone1       scheme1;
        faceZone2       scheme2;
        ...
        faceZoneN       schemeN;
    }
    .
    .
}

The default entry specifies the background scheme; additional schemes can be set per faceZone, e.g. scheme1 is applied to facZone1, scheme2 is applied to faceZone2 etc.

Test case: Test.tgz

changed milestone to %v2412

added enhancement models tutorial labels

requested review from @Prashant

assigned to @kuti

Related to #3273 (closed)

approved this merge request

added 17 commits

• 0d36ded6...45ee161f - 16 commits from branch develop
• 1eb904fc - ENH: Added new zoneBlended scheme

Compare with previous version

mentioned in commit 8e98779d

merged

mentioned in issue #3273 (closed)