Adding README.adoc file

[kasturinarra]

Adding a README.adoc file as per rh-impact/pnt-hackathon-2022#41 @porridge could you please help merge ? thanks !!

[porridge]

I have a couple of questions @kasturinarra

• there already is a README.md in this directory, so having two READMEs side by side could be confusing
• I'm not sure how useful it is to document all the options for the optipng binary right now, if the only way to use them is via interactive container execution (which I understand is not something feasible for a typical ChRIS user).

[kasturinarra]

I have a couple of questions @kasturinarra

• there already is a README.md in this directory, so having two READMEs side by side could be confusing
  I am not sure why such a task was added then in the first place if we were not supposed to have two README files , also when i checked others repo's i do see we are having README.adoc as well, so added one. For example see here https://github.com/rh-impact/pl-deoldify/pull/3/files
• I'm not sure how useful it is to document all the options for the optipng binary right now, if the only way to use them is via interactive container execution (which I understand is not something feasible for a typical ChRIS user).
  I did mention both the ways, interactive and non-interactive.

[kasturinarra]

@porridge that being said if you think this does not make sense, i am okay to close this, thanks !!

[kasturinarra]

@porridge i spoke to @computate and based on his suggestions i have removed the README.adoc file and added some content into the README.rst which is present here. Would you mind taking a look and see if you could merge ? thanks !!