#17 patch for datefield with 8.5

[Mark Alston]

This patch fixes datefield with -iq high to be compatible with tcl8.5.

Problem:
Turns out that clock scan never returns an error in 8.5 but will just give you returns for the next month. Very bad in my opinion.

The Fix:
Replace the _lastDay portion of datefield.itk with the following which checks to see if the month has changed if the clock scan returns ok.

# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_lastDay {month year} {
# Patched to work with Tcl 8.5
set lastone 28

for {set lastone 28} {$lastone < 32} {incr lastone} {
set nextone [expr $lastone + 1]
if {[catch {clock scan $month/$nextone/$year} newdate] != 0} {
return $lastone
} else {
set datestring [clock format $newdate -format "%m/%d/%Y"]
set splist [split $datestring "/"]
if { [lindex $splist 0] != $month } {
return $lastone
}
}
}
}

Best regards,
Mark Alston