Include worker thread config options in collector docs

Author: salcock

doc/CollectorDoc.md

@@ -219,6 +219,15 @@ The basic option keys are:
                         users that do not explicitly include their domain
                         in their username will be assumed to be using the
                         address'<username>@<this domain>'.
+* gtpthreads        -- set the number of threads to use for processing GTP
+                       traffic (defaults to 1, can be set to zero to disable
+                       GTP session tracking).
+* smsthreads        -- set the number of threads to use for intercepting SMS
+                       messages (defaults to 1, can be set to zero to disable
+                       SMS interception).
+* emailthreads      -- set the number of threads to use for processing email
+                       traffic (defaults to 1, can be set to zero to disable
+                       email interception).
 
 Be aware that increasing the number of threads used for sequence number
 tracking, encoding or forwarding can actually decrease OpenLI's performance,

doc/exampleconfigs/collector-example.yaml

@@ -28,6 +28,19 @@ encoderthreads: 2
 # mediators. You probably don't need to change this.
 forwardingthreads: 1
 
+# Number of threads to use for parsing GTP traffic to intercept mobile
+# data session. Can be set to zero if the collector will not see GTP traffic.
+gtpthreads: 1
+
+# Number of threads to use for intercepting SMS messages sent over SIP
+# Can be set to zero if the collector will not see SMS over SIP.
+smsthreads: 1
+
+# Number of threads to use for parsing email traffic (SMTP, IMAP, and POP3).
+# Can be set to zero if the collector will not see email traffic, or you are
+# not required to perform email interception.
+emailthreads: 1
+
 # Set this to yes if you want to override the policy of not trusting the
 # contents of the "From:" field in SIP packets (as this field is not
 # validated and can be easily spoofed).