This allows users to disable a plugin without completely removing it.
Instead, they simply remove the `plugins/enabled/*.bash` file for the
plugin they want to disable. This continues the concept of "everything
on" while providing greater flexibility to future users.
It might be a good idea to allow turning these off by default in the
future and allowing not only the `plugins/enabled/*.bash` files but also
an array of `<plugin_name>` values that would search for
`plugins/available/<plugin_name>.plugin.bash` to enable them. That
method would make it easier for people custom tune their plugins from
within their `.bash_profile` script.
* Only load a theme file if `bobby` has been set
* Only alter `PS1` if `\[[1;34m\]\[$(scm_char)\]\[[0;32m\]\[$(scm_prompt_info)\]\[[0;34m\]\[$(rvm_version_prompt)\] \[[33;40m\]\h \[[39m\]in \[[0;32m\]\w \[[39m\]\[\n\[[0;32m\]→\[[39m\] ` has a value