Bug#886712: Python3 support broken

[Ondřej Kuzník <ondra@mistotebe.net>]

Hi,
Python 3 support is still not working in testing as spatch is still
trying to load libpython2.7.

Trying to run the following trivial semantic patch:

```
@ script:python @
@@

print("Test")
```

I get this:

```
spatch --sp-file test.cocci ./
init_defs_builtins: /usr/bin/../lib/coccinelle/standard.h
Py.find_library: unable to find the Python library [libpython2.7m.so returned Library not found] [/usr/bin/../lib/libpython2.7m.so returned Library not found] [libpython2.7.so returned Library not found] [/usr/bin/../lib/libpython2.7.so returned Library not found]
```

Thanks,
Ondrej