v8.0.0

Breaking changes:

• Update project and deps to PureScript v0.15.0 (#141 by @JordanMartinez)
• Replaced polymorphic proxies with monomorphic Proxy (#141 by @JordanMartinez)

New features:

• Add coerced (#140 by @ozkutuk)
• Add sans and both (#97 by @xgrommx)

Bugfixes:

• Fix broken reindex for v0.15 due to Purescript PR #4033

Other improvements:

• Added purs-tidy formatter (#138 by @thomashoneyman)
• Replace manual tests with automated tests using assert (#135 by @Neppord)
• Improve documentation for united (#134 by @Neppord)
• Add guide on impredicativity explaining difference between Lens vs ALens (#136 by @i-am-tom and @JordanMartinez)