Fix two bugs in simulator & code cleaning

Bug 1: a1-interface is now runing single threaded, so need to setup a standalone callback server to test purpose
Bug 2: need to pass real ip from nginx to upstream main.py

Issue-ID: NONRTRIC-218
Signed-off-by: ecaiyanlinux <martin.c.yan@est.tech>
Change-Id: Ia04cbf6a402aff444f17ddd8e9bd41a19a687791
9 files changed