Send Email to Contacts - Layout and Usability Improvements

Simplify the Send Email form to support primary use case: Send simple message to a contact with basic formatting.

Implementation
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1. Simplify rich text editor toolbar (remove rarely used options like "Insert Table", etc.
2. Send Email and Cancel buttons should be on top and bottom, left aligned (see new layout for Contribution form etc.)
3. Reverse order of Text Message and HTML Message fields and relabel : "HTML format", "Plain-text format"
4. Convert show/hide divs to Accordion panes.:

• HTML format pane (expanded by default)
• Plain-text format pane (collapsed by default)
• Attachments pane (collapsed by default)
  5. Remove "Insert Tokens" multi-select fields from the main form. Add a small link above right corner of both message fields: "Insert token". For now this link doesn't do anything. After we get community review, the tentative plan for tokens is:
• user can insert token by entering the open-bracket character in the message input field "{". This keystroke will result in a list of tokens they can choose from and insert at the cursor position
• OR user can click the link above the message input field - which will also give them a list of tokens