BUG: pd.eval with numexpr engine coerces 1 element numpy array to scalar
Closes #10546. Used `assert_numpy_atray_equivalent` to guarantee array comparison, not scalar. This should be prior to #10542 and being changed to use `assert_numpy_array_equal` in #10542.

@jreback Can you take a look for this?
 looks ok. just a suggestion I put above (but may not be exactly correct)
