gmmproc: Don't change NULL to 0 in docs, when it's part of a longer name
gmmproc: Don't change NULL to 0 in docs, when it's part of a longer name

* tools/pm/DocsParser.pm: Don't change NULL to 0, TRUE to true,
FALSE to false, when they are part of a longer name.

GNOME/glibmm,johne53/MB3Glibmm,johne53/MB3Glibmm,GNOME/glibmm,GNOME/glibmm,johne53/MB3Glibmm,GNOME/glibmm,johne53/MB3Glibmm,GNOME/glibmm