autogen subpackage (#968)

* math utils in autogen

* cleanup

* code utils

* remove check function from code response

* comment out test

* GPT-4

* increase request timeout

* name

* logging and error handling

* better doc

* doc

* codegen optimized

* GPT series

* text

* no demo example

* math

* import openai

* import openai

* azure model name

* azure model name

* openai version

* generate assertion if necessary

* condition to generate assertions

* init region key

* rename

* comments about budget

* prompt

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Co-authored-by: Susan Xueqing Liu <liususan091219@users.noreply.github.com>