Update book to comply with best practices

[wouterj]

Some people wanted to follow the progress, so I've created a task list for at least the book articles. The quick tour will be updated by #4374 and the cookbook will not be as important as these other 2 sections, they'll properbly follow after 2.6 is released.

I've ordered them on priority.

• Controller (fixed by Update most important book articles to follow the best practices #4427 and Completely re-reading the controller chapter #4433)
• Templating (fixed by Update most important book articles to follow the best practices #4427)
• Routing (fixed by Update most important book articles to follow the best practices #4427)
• From Flat to Sf2 (fixed by Update most important book articles to follow the best practices #4427)
• Page creation (see Update page_creation.rst #4685, Update page_creation.rst #4687 and Update page_creation.rst to focus just on pages, splitting other info to separate doc #4690)
• Http fundamentals (see Comply with best practices, Round 2 #4507)
• Doctrine (fixed by Comply with best practices, Round 2 #4507)
• Form (fixed by Comply with best practices, Round 2 #4507)
• Security (no changes needed, see Update book to comply with best practices #4431 (comment))
• Validation (fixed by Update book to comply with best practices, round 3 #4779)
• Testing (fixed by Update book to comply with best practices, round 3 #4779)
• Propel (fixed by Update book to comply with best practices, round 3 #4779)
• Http Cache (fixed by Update book to comply with best practices, round 3 #4779)

[weaverryan]

Great idea!

[weaverryan]

@wouterj I just un-checked the boxes because I added my PR's to this list. This will help me keep track of my work on this as well. Thanks!

[mickaelandrieu]

@wouterj 👎 best practices are to be used for non open source projects. If we remove all the "open source best practices", this will impact a lot the quality of open sourced bundles.

Best practices is the best and the only place where we should apply them in documentation.

[fabpot]

@mickaelandrieu obviously, we disagree with you here. The documentation should be about people using Symfony for their own projects. Having a small chapter for bundle contributors might be great, but that should not be the main focus of our docs.

[wouterj]

And btw, we already have such chapter: http://symfony.com/doc/current/cookbook/bundles/best_practices.html

[mickaelandrieu]

@wouterj @fabpot aw didn't saw about best practices for reusables bundles.
So ... 👍 , despite I disagree some of this "best practices" rules.

[javiereguiluz]

@wouterj I've reviewed the chapter about Security and I've found no changes needed to comply with the new best practices. If you agree, you probably can update the TODO list of this PR to mark Security as "done". Thanks.