bug #19159 [WebProfilerBundle] Added a conflict for Http-Kernel < 3.1 (HeahDude)

This PR was merged into the 3.1 branch.

Discussion
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[WebProfilerBundle] Added a conflict for Http-Kernel < 3.1

| Q             | A
| ------------- | ---
| Branch?       | 3.1
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | silexphp/Silex-WebProfiler#94
| License       | MIT
| Doc PR        | ~

Commits
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d3f47f7 updated Http-Kernel dependency

Author: fabpot

composer.json

@@ -17,7 +17,7 @@
     ],
     "require": {
         "php": ">=5.5.9",
-        "symfony/http-kernel": "~2.8|~3.0",
+        "symfony/http-kernel": "~3.1",
         "symfony/routing": "~2.8|~3.0",
         "symfony/twig-bridge": "~2.8|~3.0"
     },