[PyQt] ANN: SIP v4.7.3 and PyQt v3.17.4 Released

[Phil Thompson]

SIP v4.7.3 and PyQt v3.17.4 have been released and are available from the 
usual places.

The changes are to allow PyQt v3 to be built with the latest SIP.

A bug fix in SIP v4.7.2 introduced a necessary incompatibility that prevented 
PyQt v3.17.3 from building. These involved workarounds for SIP limitations, 
most of which were resolved long ago. SIP v4.7.3 resolves the remaining 
limitations. If you have used similar workarounds in your own bindings then 
you may need to remove them. Only comparison operators are affected.

Phil