[Issue 1191][Consumer] allow override the Schema Creator by a consumer

[adrianiacobghiula]

a consumer might want to use different implementation of a Schema

Motivation

A consumer should be allowed to select / choose / override the default Schema. For example select to use https://github.com/hamba/avro and not github.com/linkedin/goavro/v2

Modifications

Add options to

Verifying this change

• [ ] Make sure that the change passes the CI checks.

(Please pick either of the following options)

This change is already covered by existing tests, such as (please describe tests).

Does this pull request potentially affect one of the following parts:

If yes was chosen, please highlight the changes

• Dependencies (does it add or upgrade a dependency): no
• The public API: no
• The schema: no
• The default values of configurations: no
• The wire protocol: no

Documentation

• Does this pull request introduce a new feature? yes
• If yes, how is the feature documented? GoDocs