minor symfony#9041 Update best_practices.rst (SergeyPodgornyy, javiereguiluz)

This PR was submitted for the 4.0 branch but it was merged into the 2.7 branch instead (closes symfony#9041).

Discussion
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Update best_practices.rst

Commits
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69e78f4 Added minor clarification about what StudlyCaps is
26ff10b Update best_practices.rst

Author: javiereguiluz

bundles/best_practices.rst

@@ -37,7 +37,7 @@ A namespace becomes a bundle as soon as you add a bundle class to it. The
 bundle class name must follow these simple rules:
 
 * Use only alphanumeric characters and underscores;
-* Use a CamelCased name;
+* Use a StudlyCaps name (i.e. camelCase with the first letter uppercased);
 * Use a descriptive and short name (no more than two words);
 * Prefix the name with the concatenation of the vendor (and optionally the
   category namespaces);