Support definition of mappings and responses in the values.yaml file

[subigre]

This PR implements the feature requested by @tom-intermedia in the issues #44, meaning it supports the definition of mappings and responses through the values.yaml file.

References

Closes #44

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[subigre]

PS: I know that I put the same chart version in both PRs (this one and the #48), but I don't know which one will be merged first.
So, I will rebase and update the version to 1.3.0 in the one that will be merged at the end (or you can do it as well)

[gitkent]

PS: I know that I put the same chart version in both PRs (this one and the #48), but I don't know which one will be merged first. So, I will rebase and update the version to 1.3.0 in the one that will be merged at the end (or you can do it as well)

The other PR has been merged. Please rebase this one and bump the chart version. thanks

[subigre]

It is done!