ENH: additional 'nocopy' methods for List resize/reserve methods

- the size of a List often requires adjustment prior to an operation,
  but old values (if any) are not of interest and will be overwritten.

  In these cases can use the _nocopy versions to avoid additional memory
  overhead of the intermediate list and the copy/move overhead of
  retaining the old values (that we will subsequently discard anyhow).

  No equivalent for PtrList/UPtrList - this would be too fragile.

- add swap DynamicField with DynamicList

BUG: fixed Dynamic{Field,List} setCapacity corner case

- for the case when the newly requested capacity coincides with the
  current addressable size, the resize of the underlying list would have
  been bypassed - ie, the real capacity was not actually changed.

- remove (unused) PtrDynList setCapacity method as too fragile

applications/test/DynamicList2/Make/files

@@ -0,0 +1,3 @@
+Test-DynamicList2.C
+
+EXE = $(FOAM_USER_APPBIN)/Test-DynamicList2

applications/test/DynamicList2/Make/options

@@ -0,0 +1,2 @@
+/* EXE_INC = */
+/* EXE_LIBS = */

applications/test/DynamicList2/Test-DynamicList2.C

@@ -0,0 +1,155 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2021 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/>.
+
+Description
+    Test allocation patterns when reading into an existing list.
+
+\*---------------------------------------------------------------------------*/
+
+#include "DynamicList.H"
+#include "DynamicField.H"
+#include "IOstreams.H"
+#include "ITstream.H"
+#include "OTstream.H"
+#include "StringStream.H"
+#include "FlatOutput.H"
+#include "ListOps.H"
+#include "labelRange.H"
+#include "labelIndList.H"
+
+using namespace Foam;
+
+template<class T, int SizeMin>
+void printInfo
+(
+    const word& tag,
+    const DynamicList<T, SizeMin>& list,
+    const bool showSize = true
+)
+{
+    Info<< '<' << tag;
+    if (showSize)
+    {
+        Info<< " size=\"" << list.size()
+            << "\" capacity=\"" << list.capacity() << "\"";
+        if (list.cdata())
+        {
+            Info<< " ptr=\"" << name(list.cdata()) << "\"";
+        }
+        else
+        {
+            Info<< " ptr=\"nullptr\"";
+        }
+    }
+    Info<< '>' << nl << flatOutput(list) << nl
+        << "</" << tag << ">\n" << endl;
+}
+
+
+template<class T, int SizeMin>
+void printInfo
+(
+    const word& tag,
+    const DynamicField<T, SizeMin>& list,
+    const bool showSize = true
+)
+{
+    Info<< '<' << tag;
+    if (showSize)
+    {
+        Info<< " size=\"" << list.size()
+            << "\" capacity=\"" << list.capacity() << "\"";
+        if (list.cdata())
+        {
+            Info<< " ptr=\"" << name(list.cdata()) << "\"";
+        }
+        else
+        {
+            Info<< " ptr=\"nullptr\"";
+        }
+    }
+    Info<< '>' << nl << flatOutput(list) << nl
+        << "</" << tag << ">\n" << endl;
+}
+
+
+template<class T, int SizeMin>
+void readList
+(
+    DynamicList<T, SizeMin>& output,
+    const UList<T>& input
+)
+{
+    OTstream os;
+    os << input;
+    ITstream is("input", os.tokens());
+
+    is >> output;
+}
+
+template<class T, int SizeMin>
+void readList
+(
+    DynamicField<T, SizeMin>& output,
+    const UList<T>& input
+)
+{
+    OTstream os;
+    os << input;
+    ITstream is("input", os.tokens());
+
+    is >> output;
+}
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+// Main program:
+
+int main(int argc, char *argv[])
+{
+    //
+    {
+        DynamicList<label, 64> list1;
+
+        list1.resize(4);
+        ListOps::identity(list1);
+
+        list1.resize(3);
+        printInfo("", list1);
+
+        // list1.clear();
+        // printInfo("", list1);
+
+        list1.setCapacity(3);
+        printInfo("", list1);
+    }
+
+    Info<< "\nEnd\n";
+
+    return 0;
+}
+
+
+// ************************************************************************* //