Merge pull request purescript-contrib#8 from purescript-contrib/lens-…

…updates

Update dependencies, use latest lens

add new combinator for making common case easy

Merge pull request purescript-contrib#5 from jdegoes/master

add a bunch of missing instances, update dependencies

export more shit

cleaned up data constructors for JCursor

added some missing instances to JCursor

added missing file

Merge pull request purescript-contrib#4 from jdegoes/ready/jcursor

added JCursor stuff & tests, also improved speed of equality tests for J...