parseJSON for the variations on ISO-8601 dates as listed in ECMA-262.
toJSON for ZonedTime limits the milliseconds to three digits
Added eitherDecode and eitherDecode'
They are just like decode and decode' respectively
but return an error message when decoding fails.
Use the more efficient unsafeShiftR instead of shiftR when base >= 4.5
Fix #72.

Sometimes, it appears, Nullary constructors can be encoded as Null as
well as an empty array [not sure why one this!]. The Generic code, as of
49befcafc80a85b371a6e0e0d5ab4ad9b33d8778, fails when a Null is
passed for a nullary constructor. Add in a pattern match to fix this
issue.
Added functions for inspecting Values
Rewrite some parseJSON methods in terms of the new with* functions
Add elaborate guide to Data.Aeson's Haddock documentation.
Merge
Add a test case for gh-72
Merge
Merge pull request #89 from wowus/master

Added an instance for the 'Fixed' class.
Merge pull request #64 from mike-burns/iso-8601

parseJSON for the variations on ISO-8601 dates as listed in ECMA-262.
Move deriving Eq ZonedTime to a safer place
Match prevailing coding style
Merge pull request #90 from basvandijk/with

Add functions for inspecting Values
Merge pull request #69 from basvandijk/eitherDecode

Added eitherDecode and eitherDecode'
Merge pull request #91 from chrisdone/master

Add elaborate guide to Data.Aeson's Haddock documentation
Update Chris's docs
Improve introductionary documentation

De-emphasize working directly with the Value type as this is not the
common (or recommended) way to use the library, but still include
documentation on how to use it when it's called for.

Since the documentation on using generics is documented in the FromJSON
and ToJSON classes, refer to that documentation instead of only
documenting one method (which is not the preferred method anymore with
default signatures I believe).