Ever since checkin [a7eee0499a], the "::" in Ttk manpage names is replaced with an underscore upon install.
This breaks prior assumptions about manpage names and makes manpages hard to find unless one knows the secret.

$ apropos ttk | grep treeview
ttk::treeview (n) - hierarchical multicolumn data display widget
$ man ttk::treeview
man: no entry for ttk::treeview in the manual.

Also, the manpage brought up with 'man ttk_treeview' makes no mention of 'ttk_treeview', only 'ttk::treeview'.

Not cool. Why was this done? For huge base of Cygwin users?