minor #334 Remove Symfony Flex dependency from MakerBundle (danrot, weaverryan)

This PR was merged into the 1.0-dev branch.

Discussion
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Remove Symfony Flex dependency from MakerBundle

We have been confused because the documentations states that Symfony Flex is required in order to use the MakerBundle.

However, we are not using Symfony Flex in our application yet, but it was still possible to use the MakerBundle. So I would suggest to remove the part saying that Symfony Flex is a dependency.

Commits
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ee422ec adding message about dir structure
42f89c2 Update index.rst
145653d Remove Symfony Flex dependency from MakerBundle

Author: weaverryan

src/Resources/doc/index.rst

@@ -4,7 +4,9 @@ The Symfony MakerBundle
 Symfony Maker helps you create empty commands, controllers, form classes,
 tests and more so you can forget about writing boilerplate code. This
 bundle is an alternative to `SensioGeneratorBundle`_ for modern Symfony
-applications and requires using Symfony 3.4 or newer and `Symfony Flex`_.
+applications and requires using Symfony 3.4 or newer. This bundle
+assumes you're using a standard Symfony 4 directory structure, but many
+commands can generate code into any application.
 
 Installation
 ------------
@@ -83,6 +85,5 @@ adding your *own* maker command is so easy, that we recommend that. However, if
 is some extension point that you'd like, please open an issue so we can discuss!
 
 .. _`SensioGeneratorBundle`: https://github.com/sensiolabs/SensioGeneratorBundle
-.. _`Symfony Flex`: https://symfony.com/doc/current/setup/flex.html
 .. _`AbstractMaker`: https://github.com/symfony/maker-bundle/blob/master/src/Maker/AbstractMaker.php
 .. _`core maker commands`: https://github.com/symfony/maker-bundle/tree/master/src/Maker