Initial commit of API and Hooks documentation.
Added remaining api hook definitions as placeholders.
Fixed heading anchor tag links.
Fixed heading anchor tag link for hook_imagex_installkit_install_profile_modules_alter.
Renamed API.md to Hooks.md
Removed stale API
Added initial link to Hooks documentation.
Added placeholders for installation tasks, portability and contributing.
Merge pull request #138 from amcgowanca/docs/initial

Initial documentation