PROTON-487: Prevent leaks of endpoints and delivery objects in the python binding

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/trunk@1572224 13f79535-47bb-0310-9956-ffa450edef68
PROTON-524: use old-style function pointers for compatibility with older SWIG tools

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/trunk@1572226 13f79535-47bb-0310-9956-ffa450edef68
added pn_error_copy; added some asserts

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/trunk@1572740 13f79535-47bb-0310-9956-ffa450edef68
renamed pn_open to pn_endpoint_open and made it static

git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/trunk@1572742 13f79535-47bb-0310-9956-ffa450edef68
Refactored messenger's I/O in such a way that it can be driven by an
external poll/epoll/select loop as described in PROTON-525. This
involved factoring a bunch of utility I/O code out of the driver and
into a more basic I/O interface (io.h and selector.h), as well as
introducing the pn_selectable_t interface.


git-svn-id: https://svn.apache.org/repos/asf/qpid/proton/trunk@1572744 13f79535-47bb-0310-9956-ffa450edef68