the previous version of operator*() made no sense. E.g., it violated the invariant
(*ptr).foo <=> ptr->foo. The dereferencing operator now returns a reference to the pointed-to
object, rather than a pointer to it.
I also added a bool conversion operator, which can be used in testing the NULL-ness of the
pointer. Anyone wondering if that could be done in a simpler way is encouraged to read
<http://www.artima.com/cppsource/safebool.html>.
And, finally, I removed the mutable flag from the m_data member, since it does not need it.
if the xkb-extension is enabled and the user switches between his/her
keyboardlayouts fluxbox's keybhandling doesn't work well anymore because
xkeyevent.state contains also xkb-related flags and thus we have to handle
that with caution.
KeyUtils now contain 'isolateModifierMask()' to really work only on the
modifiers. why not as part of cleanMods() ? because the XLookupString return
false results, eg TextBox's would only print chars from the first
keyboardlayout.
