fix Issue 12651 - TemplateArgsOf accepts nonsensical arguments
Fix Issue 11511 - DDoc - C variadic parameters cannot be properly documented.
Fix Issue 12653 - Implement the getFunctionAttributes trait.
Fix Issue 11819 - Implement better diagnostics for unrecognized traits.
refactor IntegerExp
implicit conversions for NewExp
Fix build on OpenSolaris.

With these changes, dmd compiles on OpenSolaris 11.1.
Fix Issue 12678 - Field constness missing in diagnostics for multiple field initialization error.
[style] fix indent
[Refactoring] Change return types from int to bool
[Refactoring] Remove side-effect in searchCtor
[Refactoring] Rename scope variable to `sc2` for aggregate members
Revert "[Refactoring] Rename scope variable to `sc2` for aggregate members"

This reverts commit 22f64ce78e8825d57135e2c2fa5f9af803bc8b8e.

Reverting.