Reformatted Changes file as per CPAN::Changes::Spec

Hi Marco,

I made some changes to your Changes file, so it will conform to CPAN::Changes::Spec

* Added header line identifying the file
* Release header line starts with version, without leading 'v'
* no '-' between version and date
* Made changes into bullet list

Following this format means that various tools can more easily process your distribution automatically. For example MetaCPAN will then display the most recent changes on [your dist's page](https://metacpan.org/release/MFONTANI/JavaScript-HashRef-Decode-0.133120), which it doesn't now because it can't parse the file (compare with [Module-Path](https://metacpan.org/release/Module-Path), where it can parse the file, for example).

You can find out more about this at Brian Cassidy's [CPAN::Changes Kwalitee Service](http://changes.cpanhq.org), which is where I saw your module listed :-)

Cheers,
Neil

PS I'm doing this because I'm on a quest to help improve CPAN:

> http://questhub.io/realm/perl/quest/51f0337718ba7d3959000086