Starting work on IO#getc and other methods to support rubyspec specs
Checking string length with "if not"

instead of comparison with "" per feedback from @alex.
Un-untagging some IO#getc specs since deciding to focus on IO.sysopen
Addressing too many IO concerns at once

but definitely blaming rubyspec for the tangle.
Goofy stuff to get translation happy

including some silly checking of error return value, which works but
feels... silly.  And wrong.
Changes per feedback including untranslatable stuff and failing specs!
It is sad that these specs are failing, but readline works well enough to support the other specs.
Raising correct-er errors for when closed or EOF reached

although the specs still don't match (???)
Swapping out IO#readline implementation

with something that is still incomplete, but doesn't incorrectly rely
on IO#each_line.
Fixing line building

Go go idio(ma)tic Ruby!
Document this policy for exceptions
follow the style guide
Following style guide for raising errors

a.k.a. trying to keep up with Alex :)
Merge pull request #450 from modcloth/too-much-io-stuff

Parts of IO#getc, IO#readline, IO.new, IO.for_fd, and IO.sysopen
Merge remote-tracking branch 'upstream/master' into implement-d-flag