Update for RabbitMQ

Setup instructions improved, UI informations, message acknowledgement and message durability added.
Spelling corrections
Update Caching.md

Added a small intro to CacheCow
Merge pull request #46 from marinopalsson/patch-3

Update Caching.md
Fixing merge conflicts
Merge branch 'annaberglind-master'
Mainly fixing grammar and fixing mistakes
Merge pull request #47 from thekris121/master

Mainly fixing grammar and fixing mistakes
Merging conflitcts