Develop snort IDS and content inspect service

Develop snort IDS and content inspect service

- Initial commit to show potential structure of a sample service
- This wil be part of a larger sample application currently dubbed
Service Delivery Controller
- Docker container needs to be built and employs open-source Linux packages
- Service is deployable in Istio service mesh using provided yaml
- Control snort daemon and add custom rules with GRPC messaging
- Process snort alerts actively and send to redis and upstream service
mesh components
- Integrates a web server for better HTTP signature detection

- Improved build script for CI with variables
- Render k8s yaml snort manifest dynamically with command
line options
- Improve snort_client sample script for runtime modifications
including passing args on CLI, error checking
- Update nginx proxy interface
- Added logging to snort server and alert process

Change-Id: Ic56f9fcd9ed21f64b84b85ac8ee280d69af7b7c9
Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>