Update README.md

Fix link to docs
Merge pull request #1299 from marcaube/patch-1

[InventoryBundle] Fix link to docs
Translation shipping calculator
Merge pull request #1304 from Wasper/shipping-calculator

[ShippingBundle] Translation shipping calculator options
Missing breadcrumb translation key
Coupon translations
Merge pull request #1306 from elliot/bug/missing-translations

Missing translations
[WebBundle] Added missing translation

Added missing credit card header translation (for PayumBundle > Resources > views > Payum > Action > obtainCreditCard.html.twig)
Merge pull request #1309 from boskee/missing-credit-card-translation

[WebBundle] Added missing translation