Clarified tutorial context around introduction of `orm:schema-tool:*` commands

See: http://stackoverflow.com/questions/17473225/doctrine2-no-metadata-classes-to-process for evidence of this confusion
further tweaking of last commit
further tweaking of last commit pt.2
Merge pull request #818 from mfdj/master

Clarified tutorial context in section introducing `orm:scehma-tool:*` commands
Fixed documentation rendering

The 2 lists I've fixed render as citation in the docs: http://docs.doctrine-project.org/projects/doctrine-orm/en/latest/index.html

If I didn't make any mistake, now they should render as simple lists.
Merge pull request #821 from mnapoli/patch-4

Fixed documentation rendering
Second level cache
Extract cache config
Fix persister query cache invalidation
Fix CS and update docs
handle update/delete queries
Fix docs