Mask log trace

What does this MR do?

This adds support for masking variables. Rails API needs to annotate each variable to be masked with masked: true flag.

From now one, the trace will be delayed until we are certain that it does not contain masked output.

It uses a Trie type of search for efficient masked output search.

Why was this MR needed?

Are there points in the code the reviewer needs to double check?

Does this MR meet the acceptance criteria?

• Documentation created/updated
• Added tests for this feature/bug
• In case of conflicts with master - branch was rebased

What are the relevant issue numbers?