send_file, basename spaces and path expansion

I've just done this to start the discussion. I've tested and I'm not sure why we need the quotes. The escaping you've put in works fine for me.

```python
shutit.send_file('~/this file contains spaces home dir','SHUTIT_FILE_SPACES_TEST_BLAH_BLAH_BLAH')
```

produced this for me:

SHUTIT_shutit.tk.composer.composer#W6zrg099>ls -ltr
total 24
-rwxr-xr-x 1 root root   49 Nov 25 19:12 stop_informix.sh
-rwxr-xr-x 1 root root  362 Nov 25 19:12 start_informix.sh
-rw-r--r-- 1 root root   38 Nov 26 19:47 this file contains spaces home dir
drwxr-xr-x 6 root root 4096 Nov 26 19:48 shutit_build
-rwxr-xr-x 1 root root  140 Nov 26 19:48 start_ssh_server.sh
-rwxr-xr-x 1 root root   70 Nov 26 19:48 stop_ssh_server.sh
SHUTIT_shutit.tk.composer.composer#W6zrg099>cat this\ file\ contains\ spaces\ home\ dir 
SHUTIT_FILE_SPACES_TEST_BLAH_BLAH_BLAHSHUTIT_shutit.tk.composer.composer#W6zrg099>

Which seems to have worked OK?

Do you have a usecase which is failing that I can look into? If not merge!