wrap XmuClientWindow's XGetWindowProperty in Tk_CreateErrorHandler

to fix a rare but persistent BadWindow crash
seen on (Lenny, Lucid) Gnome desktop
often after closing another application


event sequence:
 ClientMessage: serial=42280 send_event=1 win=0x1 mtype=atom#275 fmt=32 data=0x120 0x2d044 0x1 0x0 0x0
 XmuClientWindow(win 0x1)
 ClientWin.c:65: XGetWindowProperty for atom#311 'WM_STATE' of 0x1 on :0.0 [Last=42282, next=42283]

atom#275 is WM_PROTOCOLS
without the patch, ClientWin.c:65 will provoke an error e.g.

  X Error of failed request:  BadWindow (invalid Window parameter)
     Major opcode of failed request:  20 (X_GetProperty)
     Resource id in failed request:  0x1
     Serial number of failed request:  1586296
     Current serial number in output stream:  1586296
cease "Redundant argument in sprintf" warning
Tk::MMutil: use $^X instead of $self->{PERL}

Since ExtUtils::MakeMaker 6.99_10, the PERL object member is quoted.
This caused the subsequent extraction commands to be run with an
invalid command (the perl binary *with* quotes). Unfortunately
this system() call failed silently, so the real problem showed
up in a strange dependency problem, see
https://rt.cpan.org/Ticket/Display.html?id=100044

Instead of $self->{PERL}, now simply $^X is used. Also, the
extraction commands do not fail silently anymore.

Reference to the EUMM ticket:
https://rt.cpan.org/Ticket/Display.html?id=100159
update Changes for Tk-804.032_500
inc VERSIONs
Merge branch 'fix/XmuClientWindow-BadWindow'

also in https://github.com/eserte/perl-tk/pull/10
UNOFFICIAL version bump