add connect-assets #226

https://github.com/adunkman/connect-assets
use connect-assets to compile one client-side JS file, which includes all vendor libraries #226
client-side JS: we'll have everything live under an app "global" object

#226
starting to move some variables into other files #226

Unfortunately these are all being defined as "global" variables for now.
more organization for keyboard codes
organizing modes into a hash
organize errors into a hash
they probably should be called "constants" rather than "variables"
move some segment and street variables and functions into separate files #226
Rename info_and_owners.js to info.js
moving avatar variable and functions to separate file
splitting up lots of client-side code

This really is too much for one commit, but unfortunately it's a lot of tangled dependencies.
separating out street sharing code
separating out building code
move out feedback code
move out people code
dividing out a few more undo variables
separating out print code
moving out street name code
move out gallery code