Merge pull request #153 from sandriu/2567_newsletter_all

Refs #2567 create newsletter header
merged new templates and use specific view modes for newsletter
Merge pull request #155 from claudiaifrim/newsletter_templates

merged new templates and use specific view modes for newsletter
refs #2567 - arrange content in categories and add it in two columns
Merge pull request #156 from claudiaifrim/two_columns

refs #2567 - arrange content in categories and add it in two columns
refs #2567 - cleanup (remove simplenews and scs configs)
Merge pull request #157 from claudiaifrim/cleanup_newsletter

refs #2567 - cleanup (remove simplenews and scs configs)
Refs #2567: replace footer icons with gray ones
Refs #2567: add path to Osha logo inside header
Refs #2567: refactor HTML and CSS for newsletter footer
Refs #2567: footer: add font-family Arial, center the text on last cell
Refs #2567: pink-underlined link for Osha website in footer; fix footer URLs, except for Unsubscribe
Refs #2567: increase distance between social icons in footer