getMinorVersion
Returns the minor version number of the GTK library.
For example, in GTK version 3.1.5 this is 1.
This function is in the library, so it represents the GTK library your code is are running against. Contrast with the %GTK_MINOR_VERSION macro, which represents the minor version of the GTK headers you have included when compiling your code.
Return
the minor version number of the GTK library