docs/crow/scripting: Update druid install/usage instructions

[simonvanderveldt]

Updates to the docs to match the changes in monome/druid#25

Might even make it to publish to pypi today, if I do I'll create another PR to update the docs.

[csboling]

pip will warn you here if the binary location is not on your path, but it might be good to draw attention to that warning message?

[simonvanderveldt]

You mean when ~/.local/bin or /usr/local/bin isn't on $PATH?
The hint I added here was more for tab-completion (as in someone expecting dr<tab> to show them druid but it isn't happening), but that's also a valid point. On the other hand if pip already tells the user do we need to document it as well?

[trentgill]

Looks good to me. The scripting doc will need to be updated though as we no longer know the local folder.

This also means that r and u can't use a default file (was druid/sketch.lua) unless we add some fancy behaviour to track recently uploaded files.

We're making a repo today (github.com/monome/bowery) that will house user-submitted crow scripts (including the druid examples), so i guess we should get that up asap & change the docs to reflect that setup.