make it possible to configure the phpcr config, default to enabling caching
sylius does not provide a phpcr implementation, jackalope-* does
Merge pull request #1502 from lsmith77/remove_phpcr_provide

sylius does not provide a phpcr implementation, jackalope-* does
Merge pull request #1364 from lsmith77/tweak_phpcr_config

make it possible to configure the phpcr config, default to enabling caching