Fix #296 - Only set Content-Type if body exists
fixup aws function to work in more situations
added short blurb on using aws
Merge pull request #343 from nathan-lafreniere/master

Allow AWS to work in more situations, added a note in the README on its usage
switch to a case insensitive getter when fetching headers for aws auth signing
Merge pull request #332 from Marsup/issue-296

Fix #296 - Only set Content-Type if body exists
Emit errors for anything in init so that it is catchable in a redirect.
fix bug

if you delete the body, you should also delete any existing content-type and content-length, otherwise you're sending erroneous values: e.g. content-type form-encoded, content-length 1415, empty body 
Merge pull request #355 from azylman/master

stop sending erroneous headers on redirected requests
delete _form along with everything else on a redirect
Merge pull request #360 from jgautier/master

Delete self._form along with everything else on redirect
Made it so that if we pass in Content-Length or content-length in the headers, don't make a new version
Merge pull request #361 from danjenkins/master

Don't create a Content-Length header if we already have it set
inside oauth.hmacsign: running rfc3986 on base_uri instead of just encodeURIComponent.

Essentially, all I've really changed in terms of output is that the base_uri is
encoded with the rfc3986 function before being included in the sha1 base. I was
getting 401 errors with the LinkedIn API because my signatures were wrong when
I used [field selectors](https://developer.linkedin.com/documents/field-selectors)
in an api call.
Merge pull request #362 from jeffmarshall/master

Running `rfc3986` on `base_uri` in `oauth.hmacsign` instead of just `encodeURIComponent`
Revert "Merge pull request #362 from jeffmarshall/master"

This reverts commit 32713adeb81ca7c53f5f022d23309d6eab7d1d47, reversing
changes made to 4a8150744544300f392dbf00d9f185c62ac48344.
reintroducing the WTF escape + encoding, also fixing a typo.
Merge pull request #363 from jeffmarshall/master

rfc3986 on base_uri, now passes tests
oauth fix.
Merge pull request #344 from nathan-lafreniere/master

Make AWS auth signing find headers correctly