bump version to 0.2.0. (LightwheelAI#40)

bump version to 0.2.0.

mimic-gen example: pick orange. (LightwheelAI#23)

* pick orange mimic gen .

* auto annotate in pick orange mimic.

* readme update.

add success condition in pick_orange_env. (LightwheelAI#3)

* list envs in leisaac.

* add success judgement in pick orange env.

fix: add an alternative directory retrieval method.