GP-3276 Put all C++ classes in ghidra namespace

Ghidra/Features/Decompiler/src/decompile/cpp/cast.cc

@@ -16,6 +16,8 @@
 #include "cast.hh"
 #include "op.hh"
 
+namespace ghidra {
+
 /// Sets the TypeFactory used to produce data-types for the arithmeticOutputStandard() method
 /// \param t is the TypeFactory
 void CastStrategy::setTypeFactory(TypeFactory *t)
@@ -530,3 +532,5 @@ bool CastStrategyJava::isZextCast(Datatype *outtype,Datatype *intype) const
   if (intype->getSize()>=4) return false;		// cast is not zext for int and long
   return true;
 }
+
+} // End namespace ghidra