Highlight all usages of an identifier.
Currently does not support cross files rename.
Deisgned to bring Code Refactoring capabilities to the F# Language in Visual
"Code refactoring is the process of changing a computer program's source code without modifying its external functional behavior in order to improve some of the nonfunctional attributes of the software. Advantages include improved code readability and reduced complexity to improve the maintainability of the source code, as well as a more expressive internal architecture or object model to improve extensibility." source: Wikipedia