Add support for lc (locale) param in authorization URL

[alejandrodevs]

In order to change the locale in the Microsoft IDP interface, the param lc has to be added in the authorization url.
List of supported locales: https://ss64.com/locale.html

Example URL:

https://login.microsoftonline.com/common/oauth2/v2.0/authorize?client_id=client_id&lc=10&prompt=&redirect_uri=http%3A%2F%2Fwww.example.com%2Fauth%2Fmicrosoft%2Fcallback&response_type=code&scope=https%3A%2F%2Fgraph.microsoft.com%2Fuser.read+openid+email+offline_access&state=4aLMsU9-69Hafb0QJ0AMCSQM

What do you think? @swelham

[alejandrodevs]

This is similar to what has been done in this PR: ueberauth/ueberauth_google#102.

[alejandrodevs]

@swelham Did you have the opportunity to take a look at this?

[swelham]

Hey @alejandrodevs. Sorry, I haven't had chance to look at this yet. I will aim to take a look either today or tomorrow if that works?

[alejandrodevs]

@swelham Sure, that works. My apologies if I sounded too insistent, it wasn't my intention. I just wanted to make sure this PR didn't go unnoticed.

[swelham]

No worries, this looks good to me.

I will get it shipped.