docs don't mention downloading bootstrap files

[jrocnuck]

for newcomers, it may be beneficial to add to the docs that it's up to the user/coder to download the bootstrap css/ images / js stuff and put it into their own static file paths.

[fercreek]

plx documentation u.u

[ollytheninja]

It does say "A simple Django template tag to work with Bootstrap", which sorta implies it but I agree it's not 100% clear. Maybe add a line to the readme to make it more explicit @jrocnuck