Merge branch 'master' into dtd3

* master:
  Comments added to Block class step 5
  Removing .info.yml files from steps 2 - 5
Modified exercises.
Fix typo in exercises.
Textual changes to exercises.
Merge branch 'master' into dtd3

* master:
  Fixed phpdocs, added @param statements
  Teeny tiny grammar changes.

Conflicts:
	2 forms/wizzlern_pegi/wizzlern_pegi.module
Changes to namespace exercise.
Merge branch 'dtd3'

* dtd3:
  Changes to namespace exercise.
  Textual changes to exercises.
  Fix typo in exercises.
  Modified exercises.
Use AccessResult as hook_ENTITY_TYPE_access() return value.