Fix snort rule with blank content & WR packet in alert

Fix snort rule with blank content & WR packet in alert

- Fix bug with addition of content field in rule definition
that causes rules with a blank content fields to inhibit
snort from starting successfully.
- Write more of the packet data for snort alert into Redis
- Above includes X-Real-IP, X-Forwarded-For header fields
for http traffic from proxy that shows source IP

Some packet data is missing in alerts from snort.

Change-Id: I2c5c29e514d1ca9e8e5b9b3f7990afa87c6311b9
Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>