Re #81 Clarified _tail spec
[skip ci]
Closes #81 `_tail` allows redirecting to all but the current state
Using mocha-jshint to lint project files
Linted files to pass jshint test
Revised `_sequence` test
v0.5.2 - minified/gzipped (25K/9.5K)
version bump to 0.5.2