[FEAT] Adding deprecate-merge codemod for 3.6

[rajasegar]

#21
Ember.merge predates Ember.assign, but since Ember.assign has been released, Ember.merge has been mostly unnecessary. To cut down on duplication, we are now recommending using Ember.assign instead of Ember.merge.
ember-polyfills.deprecate-merge

Before

import { merge } from '@ember/polyfills';

var a = { first: 'Yehuda' };
var b = { last: 'Katz' };
merge(a, b); // a == { first: 'Yehuda', last: 'Katz' }, b == { last: 'Katz' }

After

import { assign } from '@ember/polyfills';

var a = { first: 'Yehuda' };
var b = { last: 'Katz' };
assign(a, b); // a == { first: 'Yehuda', last: 'Katz' }, b == { last: 'Katz' }

Before merge :

• get this passing try deprecate-merge codemod ember-cli-update#709

[kellyselden]

Live! Thanks again.