update linter insert path

$ /.../bin/python /.../sublime-text-3/Packages/SublimePythonIDE/server/server.py
Traceback (most recent call last):
  File ".../bin/python", line 34, in <module>
    exec(compile(__file__f.read(), __file__, "exec"))
  File "/.../SublimePythonIDE/server/server.py", line 20, in <module>
    from linter import do_linting
ImportError: No module named linter

Import was broken because of  wrong linter.py location. It's not inside '../lib' but in the same level with server.py