Scml

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**This is an important update. All participants in SCML 2020 should upgrade to this version**

* [bugfix] Production cost is not properly discounted. This is an important issue.
All simulations were conducted using the same zero production cost for all factories.
* Speeding up tournament tests (smaller worlds)
* consistent naming of non-competitors
* Adding dynamic choice of non-competitors
* Removing random from the set of default agents
* Compatibility with NegMAS 0.6.14

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* [docs] documentation and testing update.
* [setup] Making PyQT optional.
* [setup] Requiring negmas 0.6.13.

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* [docs] Adding more tutorials
* minor. Maing the controller optional in request_negotiations
* adding score to FactorySimulator to estimate final score

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* forcing negmas 0.6.11 or newer
* documentation update
* enabling setting the mechanism parameters in SCML2020World
* bugfix in PredictionBasedTradingStrategy

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* bugfix in the CLI when running tournament2019
* bugfix in MeanERPrediction for breached contracts
* making CheapBuyer compatible with the latest negmas version
* doc update
* removing all agent logs in built-in agents to speedup simulations
* changing cli script name back to cli.py. This was done to avoid a weird import error when running configs that use the cli in pycharm
* adding profiling info snapshot to the repository

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* minor updates to be compatible with the latest negmas
* documentation update
* avoid exception if gui is not installed