Add docs for accessing behaviors.

Refs cakephp/cakephp#5264
Add context comments to table docs.
[fr] follow 73843ac - add docs for accessing behaviors
[fr] follow fd5bbda
Note the absence of plugin prefixes.
complete tranlation
add namespace
add namespace and fix typos
fix typos and formatting
complete fr translation
Merge pull request #2062 from antograssiot/3.0

Add namespace to Hash + french updates/typos
Fix incorrect usage in the docs.
Merge pull request #2051 from cakephp/add-context

Add context comments to table docs.
Merge pull request #2049 from cakephp/behavior-docs

Add docs for accessing behaviors.