* cairo/Context.cs: add ctor (IntPtr, bool owned)
* cairo/cairo-api.xml: expose cairo_t as new ownable symbol type
* generator/HandleBase.cs: implement IOwnable
* generator/IOwnable.cs: new interface for wrapping ownable types
* generator/Makefile.am: add new files to build
* generator/OwnableGen.cs: SimpleBase subclass to expose IOwnable
* generator/Parameters.cs: use IOwnable.FromNative instead of HandleBase
* generator/Parser.cs: parse ownable symbol type
* generator/ReturnValue.cs: use IOwnable.FromNative instead of HandleBase
* cairo/Context.cs: use Pattern.Handle
* cairo/Pattern.cs: expose Lookup method, Obsolete the Pointer prop and
add a new Handle prop for API consistency.
* cairo/cairo-api.xml: add Pattern symbol.
* cairo/*: merge changes to Mono.Cairo since we split back in Oct 2008.
Not much changed. Scrubbed the doc index and updated NativeMethods
to match. Commented with DONTCARE the ones we will ignore. Implemented
a few of them, including an initial Device binding. Still some work
to do, and some discovery to be done to see what happened to Xcb, Glitz,
and DirectFB surfaces and whether we need to remove those classes.