Composer file adapted for dev environment

* When developing, full elcodi/elcodi package is required. Because of elcodi/elcodi
is defined replacing all its subpackages, only elcodi/elcodi will be installed (just in dev)
* In production, just simple packages are expected to be downloaded
Merge pull request #11 from elcodi/feature/store-composer-adapted-for-development

Composer file adapted for dev environment
Removed composer.lock and added to gitignore
Merge pull request #12 from elcodi/feature/removed-composer-lock

Removed composer.lock and added to gitignore
Preparing fixtures for product variant
WIP: controllers
CartController now supports product variant
Small twig improvements
Flashbag notification at login failure
Added AJAX interaction when choosing variants
Fixed product view parameters
Updated required packages version