Bumping ProxyManager dependency to 0.5.x
Removing deprecated call to `ProxyManager\Configuration#setAutoGenerateProxies()`
Uniform functionality of `write_proxy_files` and `auto_generate_proxies` (since the latter is deprecated)
Moving up code setting the proxy namespace (used internally in the config object)
Importing test from zendframework/zf2#5198 by @blanchonvincent
Always enable proxy autoloader
Removing duplicate test case
Completely dropping `auto_generate_proxies` flag (deprecated)
Removing `auto_generate_proxies` flag from tests
Merge pull request #5858 from Ocramius/hotfix/proxy-auto-generation

Deprecate Proxy auto-generation. Close #5198