Don't emit variable definition entries for things which are only declarations.
Add decldef entries for variable declarations.

This fixes "Jump to definition" on a static class member jumping to the header instead of the actual definition.
It also avoids duplicate definitions for function parameters that are mentioned by name in the function's prototype.
Now the only the variable in the function definition counts as the definition.
Merge pull request #68 from abbeyj/testing

Don't emit variable definition entries for things which are only declara...