add BindingUtilsPackage.isUnreachableCode
JS backend: return empty expression for unreachable code during translation
JS backend: minor: improve call translation for constant receiver
JS backend: simplify conversion to int
JS backend: fix KT-4601 JS: compareTo doesn't work on Numbers

#KT-4601 Fixed
JS backend: fix KT-5738 JS backend: result of toByte() should be in the range of bytes

#KT-5738 Fixed
Remove SuppressWarning('NullableProblems') and change @NotNull annotation to @Nullable in DescriptorPredicate.apply method in order to avoid the following error...

Error:Kotlin: The following Java entities have annotations with wrong Kotlin signatures:
org.jetbrains.k2js.translate.intrinsic.functions.patterns.DescriptorPredicate boolean apply(org.jetbrains.jet.lang.descriptors.FunctionDescriptor descriptor):
    In superclass type is nullable: [FunctionDescriptor?], in subclass it is not: FunctionDescriptor