Interpolate date from push message

[cdorner]

@dyokomizo I'm using the phonegap-plugin-push plugin to send push notifications to devices.

As you can see in this issue right here phonegap/phonegap-plugin-push#407 I need a way to send the message and the device interpolate if there is some date in UTC.

It's not hard to do for android devices, I just need to think in an interesting format for the date, and that's here you enter :)

After the issue #3 I did some changes and now the date is saved in the following format 2015-12-10T22:30:00.000Z

If you have some other idea it's welcome.

[dyokomizo]

ISO 8601 is the usual standard for date formats.

[cdorner]

I implement this PR phonegap/phonegap-plugin-push#455
For now is just for Android, I hope someone implement the IOS version.

If you have some free time please take a look at the PR.

[dyokomizo]

I would make it more "pluggable", so you have a primary block of code in GCMIntentService that understands the "format(...)" syntax and pluggable classes to handle the different formats, so one could format money later without having to change this code.

[cdorner]

Made this changes, I think is a little better now.

diff-push-plugin.txt