Add rather than nest include arrays for geos

Shouldn't the contents of inc_dirs be added to geos_include_dirs rather than nested within it?

Author: Russell-Jones-OxPhys

setup.py

@@ -77,7 +77,7 @@ def checkversion(GEOS_dir):
 manually and set the variable GEOS_dir (right after the line
 that says "set GEOS_dir manually here".""" % "', '".join(geos_search_locations))
 else:
-    geos_include_dirs=[os.path.join(GEOS_dir,'include'),inc_dirs]
+    geos_include_dirs=[os.path.join(GEOS_dir,'include')] + inc_dirs
     geos_library_dirs=[os.path.join(GEOS_dir,'lib'),os.path.join(GEOS_dir,'lib64')]
 
 packages          = ['mpl_toolkits','mpl_toolkits.basemap']