Epymetheus

* MAINT: Update pytest requirement from ^6.2.5 to ^7.0.1 (92)

* MAINT: Update black requirement from ^21.11b1 to ^22.1 (90)

* MAINT: Support Python 3.10 (close 85) (86)

* MAINT: Drop Python 3.6 and update dependences (close 82) (83) (84)

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* PERF: Speedup computation of Strategy.exposure() (close 75) (77)

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* GITHUB: Fix GitHub Actions (63)

* DEP: Update pandas-datareader requirement from ^0.9.0 to >=0.9,<0.11 (65)

* DOC: Fix documentation (60)

* DOC: Update documentation