Changed composer versions to 2.3

Also removed 2.4 features
Updated Composer for Symfony CMF
Added CMF SE bundles to AppKernel
Added minimal CMF configuration
Cleanup AcmeDemoBundle
Used Alice to load fixture page
Removed controller
Removed routing file
Configured SimpleCms bundle
Integrated Menu Bundle
Added some styles
default to sqlite
Added bundles
Added homepage blocks
added DoctrineCacheBundle, updated dependencies
add tests
Removed unused assets
Updated config for Routing/SimpleCms changes
Removed sqlite db from SE
Added Home to menu