merge revision(s) r43923,r43925: [Backport #9181]

	* ext/tk/lib/tkextlib/tktable/tktable.rb: fix bug on arguments for Proc object.

	* ext/tk/sample/scrollframe.rb: forgot a Module definition.

	* ext/tk/extconf.rb: check unsupported version of tclConfig.sh/tkConfig.sh. It is because current Ruby/Tk doesn't support Tcl/Tk8.6.

	* ext/tk/extconf.rb: change search step of Tcl/Tk libraries.

	* ext/tk/lib/tk/namespace.rb: instance_exec() cannot accept a script string.

	* ext/tk/lib/tk/msgcat.rb: bug fix on treating encodings. Now, ext/tk/sample/tkmsgcat-load_rb*.rb will work.


git-svn-id: svn+ssh://svn.ruby-lang.org/ruby/branches/ruby_2_0_0@44793 b2dd03c8-39d4-4d8f-98ff-823fe69b080e