feat: multi-locale bot file structure

[zhixzhan]

Description

The first stage of supporting multi-locale, reform the bot file structure.

change from current

/ComposerDialogs
  /common
    common.lg
  /Main
    Main.dialog
    Main.lg
    Main.lu
  /DialogFoo
    DialogFoo.dialog
    DialogFoo.lg
    DialogFoo.lu
  /DialogBar
    DialogBar.dialog
    DialogBar.lg
    DialogBar.lu
  /DialogBaz
    DialogBaz.dialog
    DialogBaz.lg
    DialogBaz.lu

to

/coolbot
  coolbot.dialog          
  /language-generation
    /en-us
      common.en-us.lg
      coolbot.en-us.lg
    /fr-fr
      common.fr-fr.lg
      coolbot.fr-fr.lg 
  /language-understanding
    /en-us
      coolbot.en-us.lu 
    /fr-fr
      coolbot.fr-fr.lu 
  /dialogs
    /foo
      foo.dialog
      /language-generation
        /en-us
          foo.en-us.lg
        /fr-fr
          foo.fr-fr.lg
      /language-understanding
        /en-us
          foo.en-us.lu
        /fr-fr
          foo.fr-fr.lu

And for one dialog, the folder abstract is

    /[dialog]
        [dialog].dialog
        /dialogs/[childs]
        /language-generation
            /[locale]
                 [dialog].[locale].lg
        /language-understanding
            /[locale]
                 [dialog].[locale].lu

Task Item

refs #1922
refs #1726
close #2291

Screenshots

[zhixzhan]

Hi @cwhitten @boydc2014 @luhan2017 , after a lot of test fix, the multi-locale file structure changes is ready for review, please take a look when you guys have time.

[cwhitten]

@zhixzhan can you please resolve conflicts? at that point we will review and prioritize merging this.

[zhixzhan]

@zhixzhan can you please resolve conflicts? at that point we will review and prioritize merging this.

OK, resolved.