[1905562] [8d2c0da36d] Raise the recursion limits on regexps to allow
existing regexps "in the wild" to continue working with Tcl 8.6.
Latest example comes from DejaGnu.
[9d61624b3d]: Stop crashes when emptying the superclass slot.
Deal with the elaborate rip-apart-a-metaclass case as well.
[3611643fff]: Support TclOO in autoload mechanism.
merge trunk