url schema
refactor pastes views into paste module
added shorturl via url package/blueprint

Also refactors naming conventions.
update hilariously out-of-date requirements in the readme
add blueprint name to etag
Merge pull request #43 from buhman/shorturl

shorturl
only invalidate pastes; urls are immutable
get_digest wants the digest, not the content
Merge pull request #44 from buhman/url-bugs

url bugs
request.blueprint could be null if no routes match
replace b{64,85} with b66
Merge pull request #45 from buhman/url-bugs

request.blueprint could be null if no routes match
Merge pull request #48 from buhman/b66

replace b{64,85} with b66