docs(twilio-run:start): document custom ngrok subdomains

Author: philnash

packages/twilio-run/README.md

@@ -151,6 +151,9 @@ twilio-run --inspect
 
 # Exposes the Twilio functions via ngrok to share them
 twilio-run --ngrok
+
+# Exposes the Twilio functions via ngrok using a custom subdomain (requires a paid-for ngrok account)
+twilio-run --ngrok=subdomain
 ```
 
 ### `twilio-run deploy`
@@ -318,7 +321,7 @@ Error: What?
     at next (/Users/dkundel/dev/twilio-run/node_modules/express/lib/router/route.js:131:14)
 ```
 
-In general you'll want to use the cleaned-up stack trace since the internals might change throughout time. 
+In general you'll want to use the cleaned-up stack trace since the internals might change throughout time.
 
 
 

packages/twilio-run/src/commands/start.ts

@@ -138,7 +138,8 @@ export const cliInfo: CliInfo = {
     },
     ngrok: {
       type: 'string',
-      describe: 'Uses ngrok to create and outfacing url',
+      describe:
+        'Uses ngrok to create a public url. Pass a string to set the subdomain (requires a paid-for ngrok account).',
     },
     logs: {
       type: 'boolean',