Change hardcoded telegram API URL for CI mocks (#91)

* extended TelegramBotAdapter API to override hardcoded telegram URL for CI testing purposes

* fixed api url argument name

* change api url params order

Author: IngvarJackal

library/src/main/java/com/pengrad/telegrambot/TelegramBotAdapter.java

@@ -24,7 +24,11 @@ public static TelegramBot buildDebug(String botToken) {
     }
 
     public static TelegramBot buildCustom(String botToken, OkHttpClient okHttpClient) {
-        TelegramBotClient client = new TelegramBotClient(okHttpClient, gson(), apiUrl(botToken));
+        return buildCustom(botToken, okHttpClient, API_URL);
+    }
+
+    public static TelegramBot buildCustom(String botToken, OkHttpClient okHttpClient, String apiUrl) {
+        TelegramBotClient client = new TelegramBotClient(okHttpClient, gson(), apiUrl(apiUrl, botToken));
         FileApi fileApi = new FileApi(botToken);
         return new TelegramBot(client, fileApi);
     }
@@ -43,7 +47,7 @@ private static Gson gson() {
         return new Gson();
     }
 
-    private static String apiUrl(String botToken) {
-        return API_URL + botToken + "/";
+    private static String apiUrl(String apiUrl, String botToken) {
+        return apiUrl + botToken + "/";
     }
 }