Enhance v-bind with shorthand for values matching property name

[dgirgenti]

What problem does this feature solve?

I often find myself passing bound properties into components that are identical to some computed or data property on my current Component. In cases where a bound property's value is equivalent to the property name, it would be nice to not have to repeat the property name.

This would feel familiar to the es6 object shorthand notation which allows you to leave out values that are the same as the property name.

It can also apply and will feel familiar to attributes that commonly do not include values, like an input's checked attribute.

What does the proposed API look like?

An example can be found here: https://codepen.io/anon/pen/dgNBQK

Essentially,
<SomeComponent :someProperty="someProperty" />
would become
<SomeComponent :someProperty />

[posva]

See #2877 (comment)