ENH: cleanup codeStream - use dynamicCode, dynamicCodeContext encapsulation

Problems remain with codedFixedValueFvPatchScalarField:

- readIfModified() notices change on system/codeDict, but the
  codeProperties::setUnmodified() means that only a single entry will
  get processed

- it appears that while dlclose() may (or may not) be actually closing
  the library, there are probably still references about. This means
  that a subsequent reloading still points to the original functions
  and the lookup is not updated correctly.

etc/codeTemplates/dynamicCode/codeStreamTemplate.C

@@ -44,8 +44,8 @@ extern "C"
 {
 void ${typeName}
 (
-    const dictionary& dict,
-    Ostream& os
+    Ostream& os,
+    const dictionary& dict
 )
 {
 //{{{ begin code