Add support for uploading files.

Change-Id: I87044263b589bf8156210c5d03c1cb3e4f4425df
add file upload test

Change-Id: Iab6b17f857a56f356de54755498c859d9c631712
Merge branch 'master' of https://github.com/koush/ion

# By Koushik Dutta
# Via Koushik Dutta
* 'master' of https://github.com/koush/ion:
  add file upload test
  Add support for uploading files.