Dummy coverity modeling file.

This doesn't do anything. It is just the (well
written) comments taken from the python one
https://bitbucket.org/mirror/cpython/src/ccbe2132392b180a082c75789f38afb4174f6cb3/Misc/coverity_model.c

Code/Mantid/Build/coverity_model.c

@@ -0,0 +1,18 @@
+/* Coverity Scan model
+ *
+ * This is a modeling file for Coverity Scan. Modeling helps to avoid false
+ * positives.
+ *
+ * - A model file can't import any header files.
+ * - Therefore only some built-in primitives like int, char and void are
+ *   available but not wchar_t, NULL etc.
+ * - Modeling doesn't need full structs and typedefs. Rudimentary structs
+ *   and similar types are sufficient.
+ * - An uninitialized local pointer is not an error. It signifies that the
+ *   variable could be either NULL or have some data.
+ *
+ * Coverity Scan doesn't pick up modifications automatically. The model file
+ * must be uploaded by an admin in the analysis settings of
+ * http://scan.coverity.com/projects/2832
+ */
+