use “Inbox” as page title. Not “Conversations”
use “Inbox” as page title. Not “Conversations”

closes: COREFE-173

While product was looking at the mobile responsive stuff they noticed
That this page should use the title “Inbox” to be consistent with what
We call it in the navigation and everywhere else now

Test plan:
* go to /inbox. 
* The <title> of the html document should be “Inbox”

Change-Id: I6fc958c37e59cced194f2d54b23979bbdc1f7cf8
Reviewed-on: https://gerrit.instructure.com/201254
Tested-by: Jenkins
Reviewed-by: Steven Burnett <a0b450117c5d20a22d5c4d52bb8ae13adee003d8@instructure.com>
QA-Review: Steven Burnett <a0b450117c5d20a22d5c4d52bb8ae13adee003d8@instructure.com>
Product-Review: Steven Burnett <a0b450117c5d20a22d5c4d52bb8ae13adee003d8@instructure.com>

instructure/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,instructure/canvas-lms,djbender/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,djbender/canvas-lms