aioes broken with ES 5.x

[merrellb]

It appears the fix is trivial and a few pull requests have already been submitted. I prefer the approach in:
#48

[zpoint]

Unable to add http headers with aioes
with elasticsearch==5.1.0
I can pass header as **kwargs in init

[pfreixes]

@popravich is there any plan to release the current master as a 0.6.2 aioes version or something like that ? ES 5.X was released half year ago, will be nice to have a "fixed" release :)

[popravich]

Yeah, will do a release shortly)

[popravich]

Done! https://pypi.python.org/pypi/aioes/0.7.0

[pfreixes]

this week? I would like to avoid do a reference in our requirements to a specific commit to master branch 😉