Docker: Does Docker replace the need for tools such as FAI, Salt, Ansible, Git?

Docker: Does Docker replace the need for tools such as FAI, Salt, Ansible,
Git?

A very naive question:
I'm exploring ways to automate my application deployment and management.
There seem to be many interesting tools. But I don't understand the
relative benefits and trade-offs; e.g. how they overlap functionally, how
they overlap, work together in synergy, replace one another.
In other words, where should I invest my limited learning time, place my
bets?
Many thanks,
LRP