Document .bashrc #246
Description
We have some stuff in there by default, most importantly, the part that activates the module command. We should document exactly what and why it is in this nominally user-written config file.
We should also educate our users on how having anything that isn't very simple may cause a busy login node to take a bit of time after the welcome message before you get a usable bash prompt. This includes setting a module to load by default with LMOD, or writing module load commands in the .bashrc.