* glib2: Compile schemas per directory
By changing GSETTINGSSCHEMADIR during the build setup or on single tasks
or generators, the user may place schemas in various locations. Adding a
post build function for each of this location compiles all of them
instead of only one global directory.
* glib2: Notify user about failed schema compilation
* glib2: Demo schemas installed to multiple places
A new schema lacking lacking any enumerations was introduced. Installing
it isolated simplifies the generator creation to the essential
components demonstrated.
dffischer