this patch also adds plugin_api_version to exec_flags so your plug-in can now tell if features it needs are available
more plug-ins that need this will be converted once the patch to make both the stubs and the plug-ins use the same header file is in place
git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@5809 212acab6-be3b-0410-9dea-997c60f758d6
