Changed the handling of variadic intrinsics a bit.

Removed the -fp80 option and made real be 80bit floats on X86, this is what the D spec really says it should be and fixes a bunch of issues.
Changed the handling of parameter attributes to a bit more generalized approach.
Added sext/zext attributes for byte/short/ubyte/ushort parameters, fixes #60 .
Parameter attribs now properly set for intrinsic calls if necessary.
Made the tango.math.Math patch less intrusive.
Fixed/added some mini tests.

dmd/declaration.h

@@ -642,6 +642,9 @@ struct FuncDeclaration : Declaration
     std::set<VarDeclaration*> nestedVars;
     std::string intrinsicName;
 
+    bool isIntrinsic();
+    bool isVaIntrinsic();
+
     // we keep our own table of label statements as LabelDsymbolS
     // don't always carry their corresponding statement along ...
     typedef std::map<const char*, LabelStatement*> LabelMap;