app_terminal.py:  Added GO_DIR as a default environment variable that gets set whenever a command is executed.  Should make it easier for terminal applications to figure out where things are in the event they need to reference Gate One stuff.
app_terminal.py:  Added GO_SETTINGS_DIR as a default environment variable for the same reasons as above.
gateone.js:  Updated GateOne.Utils.getEmDimensions() to include a fix for situations where <pre> elements use 'white-space: pre-wrap' instead of just 'white-space: pre'.
terminal.js:  Added some minor tweaks to how terminal sizing is calculated.
Terminal Theme CSS:  Changed the terminal class to use pre-wrap (again) so that long lines of text can wrap properly.