Fix #8570 and add test.
add missing precompile
Remove non-existent `tofirst` and `tolast` methods from adjuster API in Dates docs
Add documentation for Dates types
x::Int8=1000 now throws an error upon conversion
Fix leading_ones example
Tweak None == Union() discussion to reflect 0.4 behavior.
Merge pull request #8659 from JuliaLang/cjh/doc-types

Update type docs to 0.4-dev
handle apply_type in static_eval
deprecate `oftype(type,x)`, which is identical to `convert`