Improve documentation

[jorge07]

I would like to review the docs and explain also de concepts behind some decisions.
Things needed to explain:

• DDD objectives and reasons why.
• Core concepts like
  • bounded context
  • anti corruption layer
  • domain
  • value objects VS entities
  • aggregates
  • aggregate root
  • layered architecture and each one responsibility
  • reasons for the command and query bus
  • the event driven design
  • the application workflow
  • symfony messenger routing and testing
  • read and write models
• Add examples about advanced topics

[bareser]

I am counting the hours to read that documentation! Thank @jorge07 very much for everything you contribute to the community.

[jorge07]

After close #194 and #193 this is my next task to pick. Will take long, so I'll probably have a branch with the doc to be reviewed over time

[jorge07]

@all-contributors please add @Lutacon for code

[allcontributors]

@jorge07

I've put up a pull request to add @Lutacon! 🎉

[jorge07]

@all-contributors please add @cv65kr for code

[allcontributors]

@jorge07

I've put up a pull request to add @cv65kr! 🎉

[jorge07]

@all-contributors please add @kowalk for code

[allcontributors]

@jorge07

I've put up a pull request to add @kowalk! 🎉

[jorge07]

@all-contributors please add @patrykwozinski for code

[allcontributors]

@jorge07

I've put up a pull request to add @patrykwozinski! 🎉

[jorge07]

@all-contributors please add @jon-ht for code

[allcontributors]

@jorge07

I've put up a pull request to add @jon-ht! 🎉