download method: optional path to write file

[chaps]

When calling the download method ,
a file object is created with the same path as the requested file to download ,
paths like /Documents/somefile won't exist usually under the local filesystems where the
library is being used .

The default path to write the file contents could be the local CWD plus the name of the file being downloaded , and the method could accept a keyword argument in order to explicitly tell the desired path where to write the file contents.

[cabarnes]

@chaps Is this what you're looking for? #17

[chaps]

Hi @cabarnes ,
I'm looking for something more like this : chaps@89a816a
let me know if this fits in order to submit a PR
thanks!