Upgrade Tcl/Tk

Goal description

Tcl/Tk 8.4 has reached it's end of life, so we should make packages stop using it. This includes porting packages to be compatible with Tcl/Tk 8.5 (which is currently the default version) and 8.6 (which will be the next default). Packages which don't require specific Tcl/Tk version should not explicitly depend or build-depend on specific versions (tcl8.x/tcl8.x-dev packages). tcltk-depends helper should be used.

When all packages have migrated to newer Tcl versions, Tcl/Tk 8.4 may be deprecated (possibly removed?). Similarly, when packages surely work with Tcl/Tk 8.6, it can be probably made a default version.

Current status

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