* convert UrlEncoderUtil to be multiplatform compatible
* convert lib tests to KMP
* convert UrlEncoderTest to commonTest (but since there's only a JVM target there's no changes), and also convert mutable test data with read-only types.
* Update copyright
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Co-authored-by: Erik C. Thauvin <erik@thauvin.net>
- custom POM location removed (there are now two POMs, one for the 'Kotlin Multiplatform' publication, and another for Kotlin/JVM, and more are on the way, which would lead to a cluttered build dir)
- renamed the directories (the directory name is how Kotlin Multiplatform chooses the published artifact ID, and there's no an easier way to change it.)
- updated README examples, and link to `-jvm` variant guide
