Added caution about using is_granted in error pages
Fixed wrong link syntax
Renamed warning to caution blocks
Added PHP config format
Fixed spacing issues
Added namespaces to examples
Fixed a formatting issue in the interface name
Merge pull request #2095 from stof/patch-3

Fixed a formatting issue in the interface name
Remove repeated include
Merge pull request #2079 from WouterJ/issue_2078

[2.1] Added caution about using is_granted in error pages
[#2079] Tweaking language, adding "ok" example
Merge pull request #2080 from WouterJ/patch-33

Fixed wrong link syntax
Merge pull request #2081 from WouterJ/warning_to_caution_21

[2.1] Renamed warning to caution blocks
Merge pull request #2083 from WouterJ/add_ref_php_format

Added constraints PHP format and some code tweaks
[#2083] Fixing slight typo thanks to @l3l0
Merge branch '2.0' into 2.1

Conflicts:
	reference/constraints/All.rst
	reference/constraints/Collection.rst
	reference/constraints/Email.rst
Removing some outdated references to MinLength
[#2083] Fixing typo
Merge branch '2.0' into 2.1
Merge branch '2.1'