Introduce -localhost resp. -l abbreviation

This increases the chances of lazy people still using a security-relevant
setting.

README.md

@@ -188,6 +188,8 @@ Options:
 
 -H --host HOST        Bind address HOST (default=*)
 
+-l --localhost        Same as "--host localhost"
+
 -d --dir DIRECTORY    Serve the contents of DIRECTORY (default=cwd)
 
 -u --url MOUNTURL     Serve the contents at MOUNTURL mount path (default=/)
@@ -281,6 +283,6 @@ traversal, then you are encouraged to please refactor so that you do
 not depend on having `..` in url paths, as this tends to expose data
 that you may be surprised to be exposing.
 
-Consider using the `--host localhost` setting if you don't want other
+Consider using the `--localhost` setting if you don't want other
 people on your local network to read the files served by the command
 line server.  This may become the default in a future major version.

bin/server.js

@@ -27,6 +27,11 @@ for (var i = 2; i < process.argv.length; i++) {
       }
       break
 
+    case '-l':
+    case '--localhost':
+      host = 'localhost'
+      break
+
     case '-d':
     case '--dir':
       dir = process.argv[++i]
@@ -108,6 +113,8 @@ function help () {
 ,''
 ,'-H --host HOST        Bind address HOST (default=*)'
 ,''
+,'-l --localhost        Same as "--host localhost"'
+,''
 ,'-d --dir DIRECTORY    Serve the contents of DIRECTORY (default=cwd)'
 ,''
 ,'-u --url /url         Serve at this mount url (default=/)'