Improve some of the examples on https://documentation.magnolia-cms.com/display/DOCS/ToolsSubApp+descriptor page.

"i18n tool"
Reloading i18n messages bundles requires a lot of resources and is not the best idea.
And i18n as a tool name may also confuse some people.
FormToolDefinition needs to be explained better.

"Helloworld"
Change this into a form which allows to change properties from some <module>/configuration/<item>s stored on the configuration ws.
And highlight the beauty of the form-ui api.