added test for /api/diag REST endpoint
added test for /api/diag REST endpoint

steveyen/cbft,couchbaselabs/cbgt,couchbaselabs/cbft,couchbaselabs/cbft,couchbaselabs/cbft,steveyen/cbft,steveyen/cbft,nimishzynga/cbgt,nimishzynga/cbgt,steveyen/cbft,couchbaselabs/cbgt,nimishzynga/cbgt,couchbaselabs/cbgt,nimishzynga/cbgt,couchbaselabs/cbgt,steveyen/cbft,couchbaselabs/cbft