Correct more words in comments plus pathnames

Problem/Motivation

Found more words in the dictionary of spelling errors that are only used in comments.

Steps to reproduce

Proposed resolution

1. databasename
2. descoping
3. entitytype
4. filesort
5. hostnames
6. jumplinks
7. libmysqlclient
8. multipage
9. negotiatiors
10. pathnames - also used in method names. Included here for readability of example.sites.php
11. spacebar
12. turbolinks
13. typehinted
14. typehints
15. updatetype
16. usecase

Merge request link

Remaining tasks

Review

User interface changes

API changes

Data model changes

Release notes snippet