Deprecate hook_hook_info()

Objective

1. #1892574: Remove hook_hook_info_alter() was removed a long time ago already.

2. hook_hook_info() only exists for lazy-loading legacy hook implementation code.

3. hook_hook_info() has architectural problems causing code to not be loaded (see related issues).

4. ModuleHandler apparently maintains two cache items; one for 'module_implements', and another one just for 'hook_info'.

5. Object-oriented code can be properly auto-loaded in D8.

Remaining implementations

1. system_hook_info() (hook_token*())
2. views_hook_info() (hook_views_*())

Proposed solution

1. Remove hook_hook_info() + persistent caching from ModuleHandler.

2. Convert remaining affected hook implementations...

   A) Either move them into .module files.

   B) Or find a simple object-oriented replacement pattern.