Result of the running inspections and fixing meaningful warnings

[ermolenkodev]

I have used this inspection profile

<component name="InspectionProjectProfileManager">
  <profile version="1.0">
    <option name="myName" value="Project Default" />
    <inspection_tool class="Destructure" enabled="true" level="INFO" enabled_by_default="true" />
    <inspection_tool class="DirectUseOfResultType" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="EmptyDirectory" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="FromClosedRangeMigration" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="IncompleteDestructuring" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="InconsistentLineSeparators" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="IncorrectFormatting" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="KDocMissingDocumentation" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="KotlinLoggerInitializedWithForeignClass" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="LongLine" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="NonExhaustiveWhenStatementMigration" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="ProblematicWhitespace" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="ProhibitJvmOverloadsOnConstructorsOfAnnotationClassesMigration" enabled="true" level="ERROR" enabled_by_default="true" />
    <inspection_tool class="ProhibitRepeatedUseSiteTargetAnnotationsMigration" enabled="true" level="ERROR" enabled_by_default="true" />
    <inspection_tool class="ProhibitTypeParametersForLocalVariablesMigration" enabled="true" level="ERROR" enabled_by_default="true" />
    <inspection_tool class="ProhibitUseSiteTargetAnnotationsOnSuperTypesMigration" enabled="true" level="ERROR" enabled_by_default="true" />
    <inspection_tool class="PublicApiImplicitType" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="RedundantInnerClassModifier" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="RedundantLabelMigration" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="RedundantNotNullExtensionReceiverOfInline" enabled="true" level="INFORMATION" enabled_by_default="true" />
    <inspection_tool class="ReplaceCollectionCountWithSize" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="ReplaceNotNullAssertionWithElvisReturn" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="RestrictReturnStatementTargetMigration" enabled="true" level="ERROR" enabled_by_default="true" />
    <inspection_tool class="TodoComment" enabled="true" level="WARNING" enabled_by_default="true" />
    <inspection_tool class="UnusedMainParameter" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="WarningOnMainUnusedParameterMigration" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
    <inspection_tool class="WhenWithOnlyElse" enabled="true" level="WEAK WARNING" enabled_by_default="true" />
  </profile>
</component>

Many issues were found, but not all of them looked useful, so I fixed only part of the warnings. Fixes mostly fall into one of these categories:

• Fix typos reported by IDEA inspection
• Naming convention fixes
• Add missed KDocs
• Remove unused code
• Add KDocs for public declarations
• Fix formatting warnings