Opens a library given by tag. This is mainly meant as a shortcut so other system modules don't have to contain the complete library name string, to save ROM space. Additionaly, this call can be used to get a pointer to one of the system copyright notices and other strings.
All libraries will be opened with version number 0.
If the library cannot be opened the first try, this function calls FindResident and InitResident on the library, and tries again.