Introduces a new member function, FbWindow::cardinalProperty()
This change also changes other code that previously used
FbWindow::property() to do the same thing as the new function; this
reduces code duplication.
There are still some bits of code (Ewmh.cc, extractNetWmIcon()) that use
FbWindow::property() to retrieve XA_CARDINAL values, but as the new
method is designed for getting a _single_ property, and that code uses
FbWindow::property() to retrieve the number of values present, and then
grab all of them; it's a different use case. I opted to not try to make
cardinalProperty() into some monolithic all-purpose cardinal method;
FbWindow::property() works just fine for that.
This change also adds an optional (default=NULL) boolean to
FbWindow::textProperty and friends that allows the caller to determine
whether or not a value was actually retrieved. This was necessary for
integrating FbWindow::cardinalProperty with the codebase, and it seemed
to fit with FbWindow::textProperty as well. Prior to this change, if
you got a return value of "", you wouldn't know if you successfully
retrieved the value which happened to be blank, or if you failed to
retrieve the value. Now, you can pass the address of a boolean if you
so choose in order to differentiate these situations; the same applies
to the new FbWindow::cardinalProperty().
these two allow 'tagging' of arbitrary windows with 'tags' (or 'labels'). such 'tagged' windows can then be used in ':NextWindow (@PROP=foo)' commands to quickly cycle through a subset of available windows.
since the 'tags' are applied as real xproperties to a window they survive a restart of fluxbox or even another windowmanager. the user can also set the tags by using xprop(1).
the next step regarding the UI should be to visualize the tags of a window.
