enable offline production of summary pages

[sybenzvi]

By default, Nightwatch pages generated with bokeh require access to several JavaScript files in order to produce plots. The list of files can be identified by running

from bokeh.resources import CDN
CDN.js_files

This breaks the plots when Nightwatch is run offline, for example due to a network failure at KPNO. The fix is to define the environment variable

BOKEH_RESOURCES=inline

when running Nightwatch. The variable can be defined in the script /n/home/datasystems/setup_nightwatch.sh or in the desimodules/main config file.