Add where_or function

[pleshevskiy]

Your library is cool, but lacks the ability to do an OR.

It would be great if you could add where_or function

[despawnerer]

I had considered something like this but it's not very clear to me how it would interact with regular and-ing of conditions.

In a chain of .where_("x = 1").where_or("y = 2").where_("z = 3") what would be the expected result?