Update default folder when Creating a new bot

[yochay]

Version

cd1cc71 (from Master 10/30/2019)

Describe the bug

When creating a new bot, use a dedicated folder that is outside of Composer repo. The default project folder for new bots should not be MyBots under Composer.

For windows use %userprofile%\Documents\Composer\

• create the folder if doesn't exists

For Mac it should be in /user/documents/composer

• create the folder if doesn't exists

[cwhitten]

addressed in #1548