[LICENSE] Add name of copyright owner and date

[flaminestone]

Can you add name of copyright owner and date information to license file in package please. At now, there are only placeholder in this place
https://github.com/appknox/pyaxmlparser/blob/master/LICENSE#L189

[subho007]

Fixed in #58

[subho007]

Ref: https://www.apache.org/licenses/LICENSE-2.0.html