refactoring for better code understanding

line $entity[strlen($entity)-1] == "/" is not so obvious
add phpdoc to $bundle var in GeneratorController::generateModelAction

i did it for code-complete feature
Refactoring GeneratorController::generateModelAction

- rename $entity in $configEntityLine
- rename $entity in else block in $entityClassName
add phpdoc to $file var in GeneratorController::generateModelAction