Add full support for uniforms with initializers, including intra-stage link validation of aggregate constant initializers.

This included 
 - encapsulating aggregate constants
 - removal of constant-aggregate comparison algorithms, instead using a flattened and direct std::vector comparison
 - adding structure type comparison for independently declared structures that still might match types



git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@23274 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/baseResults/400.geom.out

@@ -3,9 +3,11 @@
 0:3    Function Parameters: 
 0:5    Sequence
 0:5      EmitStreamVertex (void)
-0:5        1 (const int)
+0:5        Constant:
+0:5          1 (const int)
 0:6      EndStreamPrimitive (void)
-0:6        0 (const int)
+0:6        Constant:
+0:6          0 (const int)
 0:7      EmitVertex (void)
 0:8      EndPrimitive (void)
 0:?   Linker Objects