Add examples to the Combinators page

[dalefrancis88]

Description

location: 'docs\src\pages\docs\functions\combinators.md'

Most Combinators are missing their examples. We need to get them added to help with new people coming on to the library

Task List

• [x] applyTo
• [x] composeB
• [x] constant
• [x] flip
• [ ] identity
• [x] substitution

For more information, see the CONTRIBUTING guide.

Further Information

This was sourced from https://github.com/evilsoft/crocks/issues/42