#6945528 Add instructions step for Jetpack manual activation flow

Changes proposed in this Pull Request

• Add the second step (instructions) of the post-purchase Jetpack manual activation flow.
• Create the <LicensingActivation /> component which can be reused in both the manual and automatic activation flows.

Notes

• The image on the right panel is not the correct one. I’ll replace it in a follow-up PR. This will require updating the <LicensingActivation /> component to accept the background image as a prop.
• We will have to revisit the styles for headers, paragraphs, and other elements to make sure we’re following our designs as closely as possible. We can address this in a follow-up PR. The idea would be to add these generic styles to <LicensingActivation /> rather than for each individual step.
• We need to clean client/my-sites/checkout/checkout-thank-you/style.scss since many of those styles are part of <LicensingActivation />. We should only add things to that file that are unique to a step and that do not apply to all steps (e.g., the style of the header or the logo at the top). We can deal with this in a follow-up PR.
• We need to apply the <LicensingActivation /> to the steps of the automatic activation flow (the one with the dropdown). We can do this in a follow-up PR as well.

Testing instructions

• Download this PR.
• Start Calypso with yarn start.
• Visit http://calypso.localhost:3000/checkout/jetpack/thank-you/licensing-auto-activate/jetpack_backup_daily.
• Select the I don't see my site. Let me configure it manually option from the dropdown.
• Make sure you are redirected to http://calypso.localhost:3000/checkout/jetpack/thank-you/licensing-manual-activate/jetpack_backup_daily. See captures at the bottom for a visual reference.
• Click on Continue.
• Make sure you are redirected to http://calypso.localhost:3000/checkout/jetpack/thank-you/licensing-manual-activate-instructions/jetpack_backup_daily. See captures at the bottom for a visual reference.

Related to 1201096622142517-as-1201096622142541

Captures