iOS doesn't check for response text when it pings the server

[timkim]

Just fixed a long standing issue in connect-phonegap where the server would spit out a 404 when an ios device tries to connect.

Essentially, it comes down to this function: https://github.com/phonegap/phonegap-plugin-contentsync/blob/master/src/ios/ContentSync.m#L142

Even if the server responds with a 404, the error reference remains nil since a 404 doesn't constitute as an error. So the server ping needs to also check for a correct response text.