liboauth should use strtok_r instead of strtok to support multithreaded usage

[GoogleCodeExporter]

In oauth_split_post_paramters, strtok_r should be used instead of strtok. In 
multithreaded environments, not doing so can result in failure to sign the url 
correctly (getting parameters from a url in another thread) or invalid memory 
access (strtok internal context pointing to another thread's stack).


http://linux.die.net/man/3/strtok_r

Original issue reported on code.google.com by mathieu....@pure.com on 1 Oct 2012 at 12:59