Cleanup and markup standardization.

PLUGINS.md

-Writing plugins
----------------
+## Writing plugins ##
 
 All you need to do to make a new plugin is creating an init function
 and a set of options (if needed), stuffing it into an object and
 putting it in the $.plot.plugins array. For example:
 
-    function myCoolPluginInit(plot) {
+```js
+function myCoolPluginInit(plot) {
     plot.coolstring = "Hello!";
-    };
+};
 
-    $.plot.plugins.push({ init: myCoolPluginInit, options: { ... } });
+$.plot.plugins.push({ init: myCoolPluginInit, options: { ... } });
 
-    // if $.plot is called, it will return a plot object with the
-    // attribute "coolstring"
+// if $.plot is called, it will return a plot object with the
+// attribute "coolstring"
+```
 
 Now, given that the plugin might run in many different places, it's
 a good idea to avoid leaking names. The usual trick here is wrap the
@@ -21,37 +22,38 @@ this: (function () { inner code ... })(). To make it even more robust
 in case $ is not bound to jQuery but some other Javascript library, we
 can write it as
 
-    (function ($) {
+```js
+(function ($) {
     // plugin definition
     // ...
-    })(jQuery);
+})(jQuery);
+```
 
 There's a complete example below, but you should also check out the
 plugins bundled with Flot.
 
 
-Complete example
-----------------
+## Complete example ##
   
 Here is a simple debug plugin which alerts each of the series in the
 plot. It has a single option that control whether it is enabled and
 how much info to output:
 
-    (function ($) {
+```js
+(function ($) {
     function init(plot) {
         var debugLevel = 1;
 
         function checkDebugEnabled(plot, options) {
         if (options.debug) {
             debugLevel = options.debug;
-              
             plot.hooks.processDatapoints.push(alertSeries);
         }
     }
 
     function alertSeries(plot, series, datapoints) {
         var msg = "series " + series.label;
-          if (debugLevel > 1)
+        if (debugLevel > 1) {
             msg += " with " + series.data.length + " points";
             alert(msg);
         }
@@ -67,7 +69,8 @@ how much info to output:
         name: "simpledebug",
         version: "0.1"
     });
-    })(jQuery);
+})(jQuery);
+```
 
 We also define "name" and "version". It's not used by Flot, but might
 be helpful for other plugins in resolving dependencies.
@@ -75,7 +78,9 @@ be helpful for other plugins in resolving dependencies.
 Put the above in a file named "jquery.flot.debug.js", include it in an
 HTML page and then it can be used with:
 
+```js
     $.plot($("#placeholder"), [...], { debug: 2 });
+```
 
 This simple plugin illustrates a couple of points:
 
@@ -88,8 +93,7 @@ The two last points are important because there may be multiple plots
 on the same page, and you'd want to make sure they are not mixed up.
 
 
-Shutting down a plugin
-----------------------
+## Shutting down a plugin ##
 
 Each plot object has a shutdown hook which is run when plot.shutdown()
 is called. This usually mostly happens in case another plot is made on
@@ -107,8 +111,7 @@ garbage collected yet, and worse, if your handler eventually runs, it
 may overwrite stuff on a completely different plot.
 
  
-Some hints on the options
--------------------------
+## Some hints on the options ##
    
 Plugins should always support appropriate options to enable/disable
 them because the plugin user may have several plots on the same page
@@ -120,14 +123,16 @@ If the plugin needs options that are specific to each series, like the
 points or lines options in core Flot, you can put them in "series" in
 the options object, e.g.
 
-    var options = {
+```js
+var options = {
     series: {
         downsample: {
             algorithm: null,
             maxpoints: 1000
         }
     }
-    }
+}
+```
 
 Then they will be copied by Flot into each series, providing default
 values in case none are specified.