Ignore errors when deciding whether to handle a file in global-eclim-…

[ovy]

…mode.

(While you're looking at my other stuff, ran into this problem recently)

Otherwise a bad Eclipse state can cause an Emacs session to get very unpleasant. I'm not sure exactly what the mechanism is, but basic stuff like find-file, switch-buffer and the M-x prompt (of all things) stop working with the Eclipse error.

To reproduce, define eclim--project-dir to (error something), then open a managed Java file not already open. Have the real eclim--project-dir ready; fortunately, eval-expression still works.

The user can run eclim-mode manually if they want to investigate the error, or try to do anything that needs project-dir. I think even printing a message would still be too unpleasant in that state, hence ignore.