People: Confusing styling on the Role selection dropdown

[hoverduck]

The Role selector on the Invite page looks like it's hardcoded to the preset value of Follower/Viewer. There's nothing in the visual to indicate that you can click on it to reveal a list of choices. I'd expect to see a down arrow, or a box around it, or something to direct me to tap it.

I'd also like to see a help link to http://en.support.wordpress.com/user-roles/ with the descriptions of what the different roles mean, like the one that exists on the web version of the invite page.

##### Tested on Nexus 6P, Android 6.0.1

[rachelmcr]

I'd also like to see a help link to http://en.support.wordpress.com/user-roles/ with the descriptions of what the different roles mean, like the one that exists on the web version of the invite page.

We could also write an in-app FAQ about the different roles, and potentially link from within the app to the FAQ. (I'll work on adding the FAQ in any case.)

[rachelmcr]

I added a FAQ titled "How can I add a user to my site" in Helpshift (for both Android and iOS apps). It includes a brief explanation for how to add users, and a summary of each user role with a link to the WordPress.com support page for more details.