Update discussion.md

- fixed typo
- roles 'moderator' and 'administrator' are explained as bullet points.
adding certificate info to the grade dump
pep8
formulaequationinput: add capital greek letters and hbar to calc preview
accessibility: Add `aria-describedby` to login/forgot password (LMS-602)

Also adding the email description to the login page and applying the
same aria attribute to the correspondin input on that page.

From LMS-602:

> There is additional explanatory text, marked up in a span element after
> the email input. The input elements should be explicitly associated with
> this additional text using the aria-describedby attribute. This will
> require an ID to be assigned to the span element.
accessibility: Focus on error messages in Help modal (LMS-584)

> To make this change explicit to assistive technology, focus should be
> moved programmatically to this div after it has been made visible. To
> allow the div to be focused via scripting (without adding it to the
> regular focus order that keyboard users cycle through), a tabindex=”-1”
> should be added.

> In addition, the invalid fields should be given a an
> aria-invalid="true" attribute.
accessibility: Add aria-hidden attribute to the help modal (LMS-584)

Added a 'aria-hidden="true"' attribute to the modal initially, then
toggle the value of that attribute to "false" when the modal is shown.
Also remove the attribute when the modal is closed, whether it's through
a click on the close button or on the overlay.
accessibility: Replace close modal button <div> by <a> link (LMS-582)

The close button for the modal dialog was marked up as a paragraph,
containing a graphical text character, inside two div elements, with an
associated click event. This made the button unusable for keyboard
users.

Replaced <divs> with a link element (<a role="button"), adapted the CSS
accordingly, and updated the existing <a> modal close buttons.
Clean up text of Order Confirmation E-mail.
Merge pull request #894 from edx/diana/confirmation-email

Clean up text of Order Confirmation E-mail.
accessibility: Manage keyboard focus on help modal dialog (LMS-581)

Modal dialogs should manage keyboard focus, ensuring that users can't
tab out of the modal dialog and back into the page itself (effectively
moving “behind” the dimmed modal). On the last focusable element of the
dialog, return focus back to the first focusable element.

Also move the close button to the start of the dialog's section, making
it the first focusable URL, to ensure focus matches the visual
representation of the dialog.
accessibility: Allow to close help modal with "escape" key (LMS-581)

Users should be able to close the modal with the "escape" key.
Add Learning Tools Interoperability (LTI) blade.

LTI blade allows to include LTI components to courses.
Python integration, Jasmine and acceptance tests are included.
Merge pull request #910 from edx/alex/add_lti_to_rc

Alex/add lti to rc
cleanup copy on reqs, photo, and choose pages
modal functionality for edit name on vcerts
Verification: revising textarea reset formatting and increasing close modal control size
Prevent being able to click on disabled button in IE.
Enable display of course org, num in receipt page.
Merge pull request #913 from edx/ormsbee/certs_small_ux

Small UI fixes
Fix element name conflict