Go to definition does not work properly if theory not loaded

[andriusvelykis]

Open a theory B that imports another theory A in the project (i.e. not Main) but without opening A first. Open a hyperlink to a definition defined in A: the editor is opened with A, but the cursor is at the top of the editor, not on the definition. Subsequent jump with the editor open works correctly and highlights the definition.

[andriusvelykis]

Fixed by avoiding theory reload if A is already submitted (issue #29)