QPID-5398: Fix cut 'n paste error in sys/posix/Path.cpp

Posix Path::IsAbsolute() function was checking for windows-style paths.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1548596 13f79535-47bb-0310-9956-ffa450edef68
NO-JIRA: Remove useless comments

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1549638 13f79535-47bb-0310-9956-ffa450edef68
Merge trunk into messaging-logging
WIP: Working version, with simplistic test program