[WebProfilerBundle] Add simple placeholders into search form
Added retrieval of sections
feature #10851 Added retrieval of sections (umpirsky)

This PR was squashed before being merged into the 2.3-dev branch (closes #10851).

Discussion
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Added retrieval of sections

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #10145
| License       | MIT

Commits
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7928767 Added retrieval of sections
feature #10660 [RFC][WebProfilerBundle] Add simple placeholders into search form (stloyd)

This PR was merged into the 2.6-dev branch.

Discussion
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[RFC][WebProfilerBundle] Add simple placeholders into search form

This is an RFC mostly, it's not a real feature, it's more like little helper for the profiler form, I guess that would mostly useful for _newcomers_, but sometimes even _old dogs_ could find it useful sometimes =)

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | kinda
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| License       | MIT

![form](https://cloud.githubusercontent.com/assets/67402/2655386/4637aa0c-bfe5-11e3-958e-84308217b52e.png)

Commits
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be65226 [WebProfilerBundle] Add simple placeholders into search form
Username in UsernameNotFoundException message data
feature #10427 Username in UsernameNotFoundException message data (maryo)

This PR was squashed before being merged into the 2.6-dev branch (closes #10427).

Discussion
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Username in UsernameNotFoundException message data

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Added username in UsernameNotFoundException message data

Commits
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3dfaa19 Username in UsernameNotFoundException message data
[Debug] Symfony debug extension
[Debug] a README for the debug extension
[VarDumper] algo to clone any PHP variable to a breadth-first queue
[VarDumper] symfony_debug ext. fast and memory efficient cloning algo
[VarDumper] add casters for per class/resource custom state extraction
[VarDumper] casters for exceptions representation
[VarDumper] casters for SPL data structures
[VarDumper] casters for PDO related objects
[VarDumper] casters for removing the entity manager from Doctrine proxies
[VarDumper] interface for dumping collected variables
[VarDumper] CLI dedicated dumper and related abstract
[VarDumper] HTML variant of the CLI dumper
[VarDumper] spec for json based representation of PHP vars
[VarDumper] json dumper for interoperable displaying