version of Tcl other than ActiveTcl is installed (ActiveTcl
included TclX, other Tcl distros didn't).
I'm removing the package loading test because it's hard to
come up with a package that is guaranteed to be in any Tcl installation.
Special-casing darwin and windows is ok since that leaves the
only Tk platform (X) which the test was trying to address.
Allow the user to create Tkinter.Tcl objects which are
just like Tkinter.Tk objects except that they do not
initialize Tk. This is useful in circumstances where the
script is being run on machines that do not have an X
server running -- in those cases, Tk initialization fails,
even if no window is ever created.
Includes documentation change and tests.
Tested on Linux, Solaris and Windows.
Reviewed by Martin von Loewis.