[ENHANCEMENT]: support prereleases in coerce

[Nokel81]

Currently the exported coerce function does not support having the pre release information as part of the returned data.

For example:

const { coerce } = require("semver")

// Current behaviour
coerce("1.9") // 1.9.0
coerce("1.9-dev") // throw

// Future behaviour
coerce("1.9-dev", { coercePrerelease: true }) // 1.9.0-dev