Clarify required parameter names in readme

Multiple people have been mistaking the ~add and ~del syntax to
include a keyword "TRACK" which results in creating an actual track
by that name. Add chevrons around required parameters in the syntax
documentation in order to make it clear those are parameter names
and not literal keywords.

Change-Id: I69d5b79d8d894f94919724c0f94225dbf959b20e

README.rst

@@ -20,13 +20,14 @@ easily by other people.
 User commands
 =============
 
-Anyone can privately message the bot with the following commands:
+Anyone can privately message the bot with the following commands
+(chevrons like <> denote required parameters):
 
-* ``in #TRACKNAME`` - tells the bot you are currently in the track
+* ``in <#TRACKNAME>`` - tells the bot you are currently in the track
   named ``TRACKNAME``.  This must be one of the tracks it knows about,
   for example: ``in #nova``
 
-* ``in LOCATION`` - tells the bot you are currently in a location
+* ``in <LOCATION>`` - tells the bot you are currently in a location
   which doesn't correspond to any track.  This can be any freeform
   text, for example: ``in the pub``
 
@@ -34,10 +35,10 @@ Anyone can privately message the bot with the following commands:
   However others will still be able to see when and where you checked
   out.
 
-* ``seen NICK`` - asks the bot where the user with the given IRC nick
+* ``seen <NICK>`` - asks the bot where the user with the given IRC nick
   was last seen (if anywhere).  The nick is case-insensitive.
 
-* ``subscribe REGEXP`` - subscribes for a direct message notification
+* ``subscribe <REGEXP>`` - subscribes for a direct message notification
   from the bot whenever a topic with a substring matching ``REGEXP``
   is set via the ``now`` or ``next`` commands (see below).  The exact
   string the (case-insensitive) regular expression will be matched
@@ -67,7 +68,7 @@ to people who have voice in the channel (+v).
 
 Commands follow the following format::
 
-  #TRACKNAME COMMAND [PARAMETERS]
+  #TRACKNAME <COMMAND> [PARAMETERS]
 
 Here is the list of available commands.
 
@@ -196,32 +197,33 @@ the virtual meeting location. Example usage::
 Admin commands
 ==============
 
-You have to be a channel operator (+o) to use admin commands.
+You have to be a channel operator (+o) to use admin commands (chevrons
+like <> denote required parameters).
 
 ~list
   List available track names
 
-~add TRACK [TRACK..]
+~add <TRACK> [TRACK..]
   Add new track(s)
 
-~del TRACK [TRACK..]
+~del <TRACK> [TRACK..]
   Deletes track(s)
 
-~clean TRACK [TRACK..]
+~clean <TRACK> [TRACK..]
   Removes active entries for specified track(s)
 
 ~newday
   Removes existing now/next/location/presence entries. This command is
   meant to be run at the start of a new day
 
-~motd add LEVEL MESSAGE
+~motd add <LEVEL> <MESSAGE>
   Adds a message of the day on top of the rendered page. Level must be one of
   info, success, warning or danger. Multiple messages can be provided.
 
-~motd del N
+~motd del <N>
   Removes Nth message from the top of the page (first message is number 1).
 
-~motd reorder X Y...
+~motd reorder <X> <Y> [Z...]
   Reorder messages. For example, ~motd reorder 2 1 would swap the top two
   messages, and remove any other message present.
 
@@ -231,7 +233,7 @@ You have to be a channel operator (+o) to use admin commands.
 ~emptydb
   Resets the database entirely to minimal contents
 
-~fetchdb URL
+~fetchdb <URL>
   Fetches JSON DB from specified URL. Any JSON key specified will replace
   existing data in database.