Bump 0.0.3

While here, fix the README.
Fix equality checks with unwrapped objects

Previous behavior: unwrapped comparison would raise an exception.

New behavior: unwrapped comparison returns false (unequal).
Update RSpec

* Use RSpec 3.1.x
* Use expect syntax
* Avoid operator matchers
Add experimental warning to README

Let users know that this is experimental software.
Update copyright with more precision

Mike Burns originally made this in 2011. It sat around for three years,
working perfectly fine, until Joe Ferris took it up. Now it is an
experimental thoughtbot tool, perhaps to someday go on to be a legend in
suspenders. Future work will happen at thoughtbot, by Mike and
certainly by others.
Syntax highlighting in README
Enumerable methods return Present, Blank

Returns Present or Blank where useful:

* collect (same behavior as fmap)
* each (same behavior as present)
* find_all (convert to Blank if the block doesn't match)
* grep (convert to Blank if the pattern doesn't match)
* map (same behavior as fmap)
* reject (convert to Blank if the block matches)
* select (convert to Blank if the block doesn't match)

Allows chaining Enumerable methods to get a wrapped value as well as
combining Enumerable methods with wrapped methods like `fmap`.

Producing an Array for these methods is not useful, because it's
unlikely that you'll want zero or more items (Array) in situations where
you started with either zero or one (Blank/Present).