Implement Timetracking v1.1

• Break issuable_time_tracking component into smaller components and bundle them
• Improve the help state UX to look like this: https://gitlab.com/gitlab-org/gitlab-ee/issues/985#note_16056031
• Create helpers for props existence checking https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/870#note_18534273
• Standardize on camelCase where possible, improve naming with computed values
• Be clear about using human values from the server vs client
• Address the accessibility impact of only displaying the remaining time in a tooltip and the percentage of time spent in a colored meter.
• Fix help 'Learn more' URL
• Remove polling until the rest of the sidebar can be synced properly

cc: @jschatz1

Closes https://gitlab.com/gitlab-org/gitlab-ee/issues/1263