I add to the storage the cookies that I receive on every request
I centralize the creation of the OCHTTPRequestOperation on the WebDavClient
I set the cookies on all the requests
I add a delete cookies method
I add a new variable to storage the original URL to recover the cookies in case of a redirected server
Merge pull request #43 from owncloud/OC-3831_SAML_Cookies_library

Oc 3831 saml cookies library
Merge branch 'master' into develop
Add first method to begin with download in background
Changes in downloads methods
Add commnets for the new methods
I add a protection to not try to upload a file that does not exist
Add new block methods to get the finish download event and callbacks of the progress of downloads
Merge branch 'master' into develop
Update AFNetworkig to version 2.3.1 and change setDownloadTaskCompleteBlock
Merge pull request #44 from owncloud/OC-4356_Background_server_library

I add a protection to not try to upload a file that does not exist
I added a flag to use cookies or not. I added a method to check if a server support cookies or not. I refactor how to check if a server is higher than other in a single method to be used on the check of cookies and on the share support API check
I fix a compilation error
I change the contant to use the k_version_support_cookies
Add a new parameter in download methods to set or not custom priority
Created a new unit test for download a file with session