add TupleOf type

[DetachHead]

Description

added TupleOf type using logarithmic method

had to update TS to 4.1.x as it uses recursive conditional types

Related issues:

• Resolved #161

Checklist

• [x] I have read CONTRIBUTING.md
• [x] I have linked all related issues above
• [x] I have rebased my branch

For bugfixes:

• [ ] I have added at least one unit test to confirm the bug have been fixed
• [ ] I have checked and updated TOC and API Docs when necessary

For new features:

• [x] I have added entry in TOC and API Docs
• [x] I have added a short example in API Docs to demonstrate new usage
• [x] I have added type unit tests with dts-jest

[DetachHead]

i think the failing tests are caused by changes to type alias resolution in newer typescript versions. i don't think testing types that way is very reliable since there are more changes like that coming in 4.2.

is there a way to structurally test types? none of the libraries i've tried seem to be able to do it properly, which is odd considering typescript is structurally typed...