Use of constant or expression in step priority results in missing step candidates

The code for parsing the priority attribute of the JBehave annotations assumes that the value is an integer literal. When it encounters a value that is a constant or expression, it stops parsing the file and any steps that appear after the problematic one are missed.

I don't think there's an easy way to evaluate the priority in these cases without involving the java compiler, but an improvement would be to use the default priority (or none at all) and at least parse the rest of the steps in the file.