How do I install an additional language besides English?
You need to do a couple of things. First, it's easiest to translate using a tool called poEdit. You will start by creating a new language file for your language based off of po/en_US.pot. This en_US.pot file is a list of all the English phrases in Bugdar. Once you have created this new language file, you can translate all of the various phrases in English into your language.
When you have completed translating all the phrases, you need to generate a file that your web server will understand. By default, poEdit does this each time you save your file. You need to copy the file that ends in .mo into a very specific location in Bugdar. Create a directory in locale/ named language_COUNTRY. For instance, United States english would have the name en_US. Inside of that directory, you need to create another directory called LC_MESSAGES. It is inside this LC_MESSAGES folder that you copy your .mo file. Be sure to rename it to messages.mo.
After you have moved your messages.mo file into the right place, you have to add a language in Bugdar. Go to Administration > Languages > Add New Language. Here, specify all the options and the language code is the same one that you used above.
Email messages should also be translated. These are not stored as Gettext strings, but rather are stored in the appropriate locale/ directory. You can copy the default ones found in locale/en_US to use as a guide for translating.
Note: Most web servers cache the .mo files. What this means is that if you install the language in Bugdar and then you want to make changes to your .mo file, you will have to restart the web server for the changes to take effect.