Use Route annotations

Without the use statement, this din't worked

Also I had to set the routing.yml from the bundle to::
    AcmeBasicCmsBundle:
      resource: "@AcmeBasicCmsBundle/Controller"
      type: annotation
added blank line
Fixes route demo in Router documentation 

It looks like the `/docs` route is supposed to be nested under the `/contact` route but the comment didn't reflect this.
Merge pull request #588 from harmstyler/patch-1

Fixes route demo in Router documentation
Merge pull request #577 from DoneBySimon/patch-7

Use Route annotations
add missing use statements to fixture examples
Update installation.rst

Adding notice that the AcmeDemoBundle is only accessible in the dev environment. So that newbies are less likely to see an Exception right from the start.
Explain why dev environement is necessary
cleanup link to symfony
Merge branch 'patch-1'
Merge pull request #589 from symfony-cmf/add-missing-use-statements

add missing use statements to fixture examples
Merge branch 'master' into dev