[Issue #963] Perform default handling for NSURLAuthenticationMethodDefault authentication challenges

Signed-off-by: Mattt Thompson <m@mattt.me>
Merge branch 'master' of github.com:AFNetworking/AFNetworking
[Issue #942] [Issue #943] Don't attempt to use URL-encoded credentials in connection:didReceiveAuthenticationChallenge:, since any included credentials would have to be invalid to have an authentication challenge be issued

Signed-off-by: Mattt Thompson <m@mattt.me>
Implement initial unit testing and continuous integration system for AFNetworking. refs AFNetworking/AFNetworking#941
Add Travis CI build status logo to README.md
Remove unnecessary CocoaPods setup during Travis build execution
Cleanup Podfile and remove overridden OTHER_LDFLAGS on AFNetworking static library target
Restore previous break-out of Pods configuration as the global import links it into the wrong targets
Add Podfile.lock to the project
Reorganize testing setup

* Eliminate static library and framework targets
* Migrate all testing infrastructure and code to Tests/
* Nest CocoaPods setup for testing under Tests/
* Remove explicit dependencies from shared schemes
Restore functionality of Rake tasks
Add section to the README.md detailing how to setup and execute the unit tests
Fixed a leak in requestWithMethod:path:parameters:

`CFStringConvertEncodingToIANACharSetName` is documented to follow CF’s create-rule, so the cast needed to be transferring ownership to ARC.
Merge pull request #989 from danyowdee/master

Fix for leaked strings in -[AFHTTPClient requestWithPath:method:params:]
Revert "Fixed a leak in requestWithMethod:path:parameters:"

This reverts commit fad9a6249c4bfc75250459575214123890475947.
Add test coverage for construction of request body via `AFHTTPClient`. refs #989
Add test coverage around operation cancellation setting the error and invoking the failure block. refs #941
Pull in a few more basic request/response tests from @kcharwood
Add composite status code reporting during CLI execution
Adjust delays on cancellation test -- unsure why this does not pass when run in the full suite