0.3.0

CHANGES:

---

• Add MPSC queue (@lyrm)
• Add SPSC queue (@bartoszmodelski)
• Add MPMC relaxed queue (@bartoszmodelski, @lyrm)
• Add Michael-Scott Queue (@tmcgilchrist, @bartoszmodelski, @lyrm)
• Add Treiber Stack (@tmcgilchrist , @bartoszmodelski, @lyrm)
• Integrate model-checker (DSCheck) (@bartoszmodelski)