createAbstractDataSource function
Implementation
void createAbstractDataSource(String title, dir) {
String newTitle = capitalize(title);
print("--Writing $newTitle abstract datasource......");
String abstractDataSourceTemplate = '''
abstract class ${newTitle}DataSource {
}
''';
File("${dir.path}/${title.toLowerCase()}_datasource.dart")
.writeAsStringSync(abstractDataSourceTemplate);
}