Use "--config ui.report_untrusted=false" for hg calls in hgk, fixes issue523. tcl's exec yields an error if output to stderr happens and isn't redirected to a file, so the warnings about untrusted .hg/hgrc caused problems in hgk. The warning is still printed when executing 'hg view', so the user can see it when using it from the shell.

Added full URL to debug output if something doesn't look like an http hg repo. This way it is easier to debug problems with failing subcommands, like changegroupsubset due to permission problems, when generally accessing the repository works fine.