Remove unnecessary dependencies

[adroitwhiz]

This PR removes the dependencies on string.prototype.trim and for-each.

for-each contains utilities to iterate over strings, arrays, and objects, and contains checks to handle lots of corner cases, but this package doesn't need any of that because it only iterates over one simple array.

string.prototype.trim pulls in 13 dependencies. These add up to 16KB minified/4KB gzipped. The one-line function I replaced it with is equivalent to the original trim package removed in #6.

[kesla]

Thank you!!