ENH: read support for EnSight single-file transient (#3154)

- the ensightReadFile init() now automatically sets up binary/ascii
  (for geometry files) and checks for the transient "BEGIN TIME STEP"
  marker. If found, will also populate the file offsets for each of
  the timesteps.  If no corresponding footer is found (which would be
  very inefficient), it simply pretends that there is only a single
  time step instead of performing a costly file scan.

- parsing of the ensight case file now also supports the use of

      filename numbers:

  as an alternative to

      filename start number:
      filename increment:

- improved parsing robustness of "time values:" entry.
  Can now also have contents on the same line as the introducer.

ENH: base-level adjustments for writing transient single-file

- beginGeometry() is now separated out from file creation.

- in append mode, ensightFile and ensightGeoFile will attempt to
  parse existing time-step information.

applications/test/ensightFileName/Make/files

@@ -0,0 +1,3 @@
+Test-ensightFileName.cxx
+
+EXE = $(FOAM_USER_APPBIN)/Test-ensightFileName

applications/test/ensightFileName/Make/options

@@ -0,0 +1,5 @@
+EXE_INC = \
+    -I$(LIB_SRC)/fileFormats/lnInclude
+
+EXE_LIBS = \
+    -lfileFormats

applications/test/ensightFileName/Test-ensightFileName.cxx

@@ -0,0 +1,79 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2016 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Application
+    Test-ensightFileName
+
+Description
+    Check cleanup of ensight file and variable names
+
+\*---------------------------------------------------------------------------*/
+
+#include "argList.H"
+#include "ensightFileName.H"
+#include "ensightVarName.H"
+#include "IOstreams.H"
+
+using namespace Foam;
+
+void printCleaning(const fileName& pathName)
+{
+    Info<< "input = " << pathName << nl;
+    Info<< "file  = " << ensight::FileName(pathName) << nl;
+    Info<< "var   = " << ensight::VarName(pathName)  << nl;
+    Info<< nl;
+}
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+// Main program:
+
+int main(int argc, char *argv[])
+{
+    argList::noBanner();
+    argList::noParallel();
+    argList::addArgument("fileName .. fileNameN");
+
+    argList args(argc, argv, false, true);
+
+    if (args.size() <= 1 && args.options().empty())
+    {
+        args.printUsage();
+    }
+
+    fileName pathName;
+
+    for (label argI=1; argI < args.size(); ++argI)
+    {
+        pathName = args[argI];
+        printCleaning(pathName);
+    }
+
+    Info<< "\nEnd\n" << endl;
+    return 0;
+}
+
+
+// ************************************************************************* //