MongoDB upgrade to 2.6 gotcha on Ubuntu

When upgrading MongoDB from version 2.4.10 to 2.6.3 on Ubuntu using the official MongoDB repository, one must notice the new package name. This is a small problem, but remember the configuration file is no longer named mongodb.conf but instead mongod.conf. A new default configuration file will be created. Remember to update this file with any changes made to the original mongodb.conf file. Also remember the default bind_ip configuration value is now 127.0.0.1 (only local access) and not 0.0.0.0 (all access).