`create_tcl_sub()` breaks command in other interpreters

[chrstphrchvz]

There are structures in Tcl.pm which fail to keep interpreter-specific information isolated between interpreter objects. One example of this is shown by the test proposed in #53: if the create_tcl_sub() method is called for different interpreters using the same command name, then the command only works in one of the interpreters.

[chrstphrchvz]

This sort of issue and how to fix it (i.e. replace all existing %anon_refs usage with an interpreter-specific alternative) was already discussed in the later replies to https://rt.cpan.org/Ticket/Display.html?id=125472