v2.8.5-rc (nameko#525)

* Update CHANGES

* Release 2.8.5

v2.8.4 rc (nameko#513)

* Update CHANGES

* Release 2.8.4

Merge pull request nameko#501 from nameko/restrict-eventlet

Restrict eventlet

Merge pull request nameko#497 from davidszotten/2.8.2-rc

Release 2.8.2

Merge pull request nameko#494 from nameko/v2.8.1rc

v2.8.1rc

Merge pull request nameko#489 from nameko/v2.8.0-rc

v2.8.0 rc

Merge pull request nameko#480 from nameko/v2.7.0-rc

v2.7.0-rc

Merge pull request nameko#434 from nameko/v2.6.0-rc

v2.6.0 rc

Merge pull request nameko#433 from nameko/v2.5.4-rc

v2.5.4 rc

Merge pull request nameko#419 from davidszotten/bump_prefetch

Bump prefetch