docs(actions): Migrated actions section from old Getting Started docs and cleaned up related sections.

Refs #6812.
docs(events): Updated event list and cleaned up existing event docs.

Refs #6812.
docs(hook): Updated hooks docs.

Refs #6812
docs(all): Added getting started for developers.

Refs #6812
docs(all): Cleanup docs.

Refs #6812.
docs(admin): Migrated Getting Started guide from wiki.

Refs #6812.
docs(faqs): Started migrating some FAQs.
chore(cleanup): removed unused $CONFIG->installer_running variable 

fixes #4973
fix(uservalidationbyemail): makes emailsent page public

Marks uservalidationbyemail/emailsent as a public page in walled garden to
ensure that newly registered users receive a understandabe comfirmation page.

Fixes #7334
Merge pull request #7358 from stianlik/uservalidationbyemail

fix(uservalidationbyemail): makes emailsent page public
Merge pull request #7240 from brettp/docs_getting_started

Docs getting started
Merge pull request #7353 from jdalsem/remove-unused-installer-running

chore(cleanup): removed unused $CONFIG->installer_running variable