Revert "Merge pull request #2646 from WalterBright/get-autotest-running"

This reverts commit 1a7ce594188fd30238a976e8d5784eb146090a6a, reversing
changes made to 511b24a4579f7cfb3fbafaa541b93a1ba67c4705.
Merge pull request #2647 from dawgfoto/fix11203

Revert "Merge pull request #2646 from WalterBright/get-autotest-running"
[trivial] fix style nitpicks
[Refactoring] Improve error check in CallExp::semantic
fix Issue 10658 - Cannot merge template overload set by using alias declaration

- Add OverDeclaration and see it in overloadApply.
- Use OverDeclaration for template overload set merging.
- Check OverDeclaration in DotVarExp and VarExp.