Add createPlaylist api call.

Signed-off-by: Yahor Berdnikau <egorr.berd@gmail.com>

subsonic-api/src/integrationTest/kotlin/org/moire/ultrasonic/api/subsonic/SubsonicApiCreatePlaylistTest.kt

@@ -0,0 +1,54 @@
+package org.moire.ultrasonic.api.subsonic
+
+import org.junit.Test
+
+/**
+ * Integration test for [SubsonicAPIClient] for createPlaylist call.
+ */
+class SubsonicApiCreatePlaylistTest : SubsonicAPIClientTest() {
+    @Test
+    fun `Should handle error response`() {
+        checkErrorCallParsed(mockWebServerRule) {
+            client.api.createPlaylist().execute()
+        }
+    }
+
+    @Test
+    fun `Should hanlde ok response`() {
+        mockWebServerRule.enqueueResponse("ping_ok.json")
+
+        val response = client.api.createPlaylist().execute()
+
+        assertResponseSuccessful(response)
+    }
+
+    @Test
+    fun `Should pass id param in request`() {
+        val id = 56L
+
+        mockWebServerRule.assertRequestParam(responseResourceName = "ping_ok.json",
+                expectedParam = "playlistId=$id") {
+            client.api.createPlaylist(id = id).execute()
+        }
+    }
+
+    @Test
+    fun `Should pass name param in request`() {
+        val name = "some-name"
+
+        mockWebServerRule.assertRequestParam(responseResourceName = "ping_ok.json",
+                expectedParam = "name=$name") {
+            client.api.createPlaylist(name = name).execute()
+        }
+    }
+
+    @Test
+    fun `Should pass song id param in request`() {
+        val songId = listOf(4410L, 852L)
+
+        mockWebServerRule.assertRequestParam(responseResourceName = "ping_ok.json",
+                expectedParam = "songId=${songId[0]}&songId=${songId[1]}") {
+            client.api.createPlaylist(songIds = songId).execute()
+        }
+    }
+}

subsonic-api/src/main/kotlin/org/moire/ultrasonic/api/subsonic/SubsonicAPIDefinition.kt

@@ -91,4 +91,9 @@ interface SubsonicAPIDefinition {
 
     @GET("getPlaylists.view")
     fun getPlaylists(@Query("username") username: String? = null): Call<GetPlaylistsResponse>
+
+    @GET("createPlaylist.view")
+    fun createPlaylist(@Query("playlistId") id: Long? = null,
+                       @Query("name") name: String? = null,
+                       @Query("songId") songIds: List<Long>? = null): Call<SubsonicResponse>
 }