refactor: upgrade lg parser and syntax

[zhixzhan]

Description

changes:

1. upgrade to latest lg-parser, changes contains renaming and bug fix.
2. use "botbuilder-lg" package-name instead of myget feed url in package dependency
3. change lgParser API {Name, Parameters}.. upper case to lower case
4. change sample bot lg syntax from [] to @{}
5. Deprecated [template ] reference syntax will not be supported anymore

syntax updated:

1. server/assets/projects/**/*.dialog
2. server/assets/projects/**/*.lg
3. lib/shared/lgUtils/{parsers,stringBuilders}
4. lib/shared/dialogIndexer

Task Item

Closes #1676
Closes #1211
Closes #1542
Fixes #1680

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• Code refactor (non-breaking change which improve code quality, clean up, add tests, etc)

Checklist

• I have added tests that prove my fix is effective or that my feature works
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have functionally tested my change

Screenshots

Please include screenshots or gifs if your PR include UX changes.

[yeze322]

I've checked those updates in '@bfc/shared -> lgUtils', no problem.