Processors api

Try to make some order in the APIs of all processors, by using a const ref to the Params object in the constructor.

Many of the usual processors are like this.

Also, try to avoid structures of Params with constructors/destructors for simplicity

added 28 commits

• 6185351d...4e207dfa - 27 commits from branch master
• 5c264822 - Merge branch 'master' into processors_api

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merged

mentioned in commit 7af28417