Fix Python init function call
Fix #8035. Sip update for plugin installer
Fix #8034. Sextante SIP update
debian packaging: replace %Module directive in header for older sip versions in squeeze and lucid (following 61e101dd4)
also update networkanalysis.sip (following 61e101dd4)
[FEATURE] Add DataUrl to layer's metadata

Like keyword list, attribution and metadata url, this information is
used by QGIS Server in WMS GetCapabilities and GetContext Request.
The user can add an url where he can find information about the layer.