Bump version number following removing of old function. It was used indirectly.

theano/sandbox/cuda/blas.py

@@ -363,7 +363,7 @@ class GpuConv(Op):
         return ['cuda_ndarray.cuh','<stdio.h>']
 
     def c_code_cache_version(self):
-        return (0,14) # raise this whenever modifying any of the support_code_files
+        return (0,15) # raise this whenever modifying any of the support_code_files
 
     def c_support_code_apply(self, node, nodename):
         # REMEMBER TO RAISE c_code_cache_version when changing any of these files