Added force open in TextMate and fixed confusion when opening an alias.

Any file should be able to be opened within TextMate, so Option-DblClick will always do that. I first noticed this being useful with .xib files.

Because of the order of the if statements, opening an alias to a package or binary file (or .xib) would not have the previous if statements applied to it. So an alias to a .xib would actually always open in TextMate, but only because of mis-ordered logic.