Remove code marks from headings

- per zfcampus/apigility-documentation#40
Merge branch 'hotfix/readme-formatting'

Removes code markers from headings
Fix: Remove unused variable
Fix: Remove unused imports
Fix: Remove unused local variable
Fix: PHPDoc comments / signatures
Merge pull request #54 from localheinz/bugfixes/unused-variable

Fix: Remove unused variable
Merge branch 'hotfix/54'

Close #54
Merge pull request #55 from localheinz/bugfixes/unused-imports

Fix: Remove unused imports
Merge branch 'hotfix/55'

Close #55
Merge pull request #56 from localheinz/bugfxies/unused-local-variable

Fix: Remove unused local variable
Merge branch 'hotfix/56'

Close #56
Merge pull request #57 from localheinz/bugfixes/php-doc

Fix: PHPDoc comments / signatures
Merge branch 'hotfix/57'

Close #57