Adds a link to the plan ledger view in the current plan information
shown in the support views. Link is not shown if the plan is 100%
sponsored, e.g., the Community plan.
Adds a formatted header area to the activity table template so
that it's easy to add useful information to these activity views.
Also, renames `ad_hoc_query.html` to `activity_table.html`,
`realm_summary_table.html` to `installation_activity_table.html`,
and `activity_details_template.html` to `activity.html`.
Removes the style attribute in the installation activity template
and uses a CSS class, "installation-activity-header", to center the
h3 and p tags instead. This removes an exception from the custom
lint check.
Lauryn Menard
Aman Agrawal