use keys instead of each to workaround perl bug

in perl before 5.14 each may panic with: attempt to copy freed scalar
order is no longer random
Merge pull request #506 from trinitum/replace-each-with-keys

use keys instead of each to workaround bug in perl
updated Changes
test EV too
more consistent hook examples
show how to pass arguments to actions
make sure worker is still active
better around_action tests
more consistent hook examples
fixed streaming recipe in cookbook
more consistent POD formatting
small optimizations
fixed Mojo::Transaction::WebSocket to generate RFC 6455 compliant Sec-WebSocket-Key headers
better tests for WebSocket handshake
added another hook example
documentation tweaks
more consistent heredocs
mention subdirectory handling in rendering guide
link to deployment recipes from tutorial