avoid extra allocation in collections mappers (#309)

Author: ErwinOlie

mappie-api/src/commonMain/kotlin/tech/mappie/api/builtin/collections/ListMappers.kt

@@ -7,12 +7,12 @@ public class IterableToListMapper<FROM, TO>(private val inner: Mappie1<FROM, TO>
     : ObjectMappie<Iterable<FROM>, List<TO>>() {
 
     override fun map(from: Iterable<FROM>): List<TO> =
-        from.map(inner::map).toList()
+        from.mapTo(mutableListOf(), inner::map)
 }
 
 public class IterableToMutableListMapper<FROM, TO>(private val inner: Mappie1<FROM, TO>)
     : ObjectMappie<Iterable<FROM>, MutableList<TO>>() {
 
     override fun map(from: Iterable<FROM>): MutableList<TO> =
-        from.map(inner::map).toMutableList()
+        from.mapTo(mutableListOf(), inner::map)
 }

mappie-api/src/commonMain/kotlin/tech/mappie/api/builtin/collections/SetMappers.kt

@@ -8,12 +8,12 @@ public class IterableToSetMapper<FROM, TO>(private val inner: Mappie1<FROM, TO>
     : ObjectMappie<Iterable<FROM>, Set<TO>>() {
 
     override fun map(from: Iterable<FROM>): Set<TO> =
-        from.map( inner::map).toSet()
+        from.mapTo(mutableSetOf(), inner::map)
 }
 
 public class IterableToMutableSetMapper<FROM, TO>(private val inner: Mappie1<FROM, TO> = generated())
     : ObjectMappie<Iterable<FROM>, MutableSet<TO>>() {
 
     override fun map(from: Iterable<FROM>): MutableSet<TO> =
-        from.map( inner::map).toMutableSet()
+        from.mapTo(mutableSetOf(), inner::map)
 }