Change command line compiler directive priority

[robertwb]

Currently a directive is set
by these precedence rules (i.e. start at the top of the list and
continue until a setting is found):

1. with statement and decorators w/ block level
2. command line switch --directive
3. #cython comment at top of file
4. builtin defaults

Now that we see what kind of things this can be used for (i.e.
cdivision), I propose that the 2) and 3) are exchanged, so that #cython
comments take precedence before command line.

Migrated from http://trac.cython.org/ticket/269

[robertwb]

@dagss changed owner from somebody to dagss
status from new to assigned
commented

[robertwb]

@dagss changed priority from major to blocker
commented

Simple change, but should be done.

[robertwb]

@dagss changed resolution to fixed
status from assigned to closed
commented

Done.