v0.3.4

• Upgrade Kotlin version up to 1.4.30
• Publish the library to Maven Central instead of Bintray #96.
• Add license information to published POMs #98.
• Implement workaround for specialized MutableEntrySet.contains/remove KT-41278.
• Bug in PersistentList - list is broken after removeAll call #92.
• Faster bulk operations for non-ordered sets (removeAll, retainAll, containsAll) #91.
• Faster addAll/putAll implementation for non-ordered sets/maps #83.
• Add extension functions to convert Sequence to persistent collections 84.
• Add missing CharSequence.toImmutableSet() extension function.