Extend templates filters

Fully remove mathjax from plugins

lib/book.js

@@ -348,6 +348,9 @@ Book.prototype.parsePlugins = function() {
     return Plugin.normalize(pluginsList)
     .then(function(_plugins) {
         that.plugins = _plugins;
+
+        // Add filters
+        that.template.addFilters(that.plugins.filters);
     });
 };
 

lib/configuration.js

@@ -6,7 +6,7 @@ var npmi = require('npmi');
 var fs = require("./utils/fs");
 
 // Default plugins added to each books
-var defaultsPlugins = ["mathjax"];
+var defaultsPlugins = [];
 
 // Normalize a list of plugins to use
 function normalizePluginsList(plugins) {

lib/template.js

@@ -66,6 +66,14 @@ var TemplateEngine = function(book) {
 	);
 };
 
+// Add filters
+TemplateEngine.prototype.addFilters = function(filters) {
+    _.each(filters, function(func, key) {
+        this.book.log.debug.ln("add filter '"+key+"'");
+        this.env.addFilter(key, func);
+    }, this);
+};
+
 // Render a string from the book
 TemplateEngine.prototype.renderString = function(content, context, options) {
     var context = _.extend({}, context, {