Increase snippet content column size.

This will fix issue #3904

db/migrate/20130611210815_increase_snippet_text_column_size.rb

+class IncreaseSnippetTextColumnSize < ActiveRecord::Migration
+  def up
+    # MYSQL LARGETEXT for snippet
+    change_column :snippets, :content, :text, :limit => 4294967295
+  end
+
+  def down
+  end
+end