Tidied imports.

gprMax/input_cmds_file.py

@@ -16,7 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with gprMax.  If not, see <http://www.gnu.org/licenses/>.
 
-import sys, os
+import os, sys
 
 from gprMax.exceptions import CmdInputError
 from gprMax.utilities import ListStream