bug #122 Move dotenv to "require" (nicolas-grekas)

This PR was merged into the 3.4 branch.

Discussion
----------

Move dotenv to "require"

This doesn't hurt anything and should ease using .env files without issues.

Commits
-------

5cd4dd8 Move dotenv to "require"

Author: nicolas-grekas

composer.json

@@ -8,13 +8,11 @@
         "ext-ctype": "*",
         "ext-iconv": "*",
         "symfony/console": "*",
+        "symfony/dotenv": "*",
         "symfony/flex": "^1.1",
         "symfony/framework-bundle": "*",
         "symfony/yaml": "*"
     },
-    "require-dev": {
-        "symfony/dotenv": "*"
-    },
     "config": {
         "preferred-install": {
             "*": "dist"