Fixed rst syntax

- `:php:method` to `:php:meth`
- fixed error `SEVERE: Duplicate ID: "namespace-Cake\Cache”.`
- delete conflict mark
Added timezone option for db config.
Fixed typo
Merge pull request #981 from okonomi/3.0-rst-syntax-fix

Fixed rst syntax
Merge pull request #982 from ADmad/3.0

Added timezone option for db config.
Add information about composite primary keys + auto increment.
Merge pull request #987 from cakephp/3.0-database-key

Add information about composite primary keys + auto increment.
General updates to table objects documentation
Merge pull request #988 from bcrowe/hotfix-tableObjects

3.0 - General updates to table objects documentation
Grammar updates to 3.0 migration guide
Fix formatting in migration guide.
Remove docs for classes that have been removed.
Add collections & validation docs to the TOC.
Fix build errors + missing files in TOC.
Move validation docs to live with other 'libraries'.
Fix more build errors.
Remove old model docs.
Remove sanitize docs.

Sanitize has been removed, update the docs.
Fix more broken links.