Rename all occurrences of the library name

[victorholo]

We got a notice that the library name is being protected by trademark and have until the beginning of December 2022 to change it to something else.

Upon internal discussions we concluded that strato will become venin (and hedera-venin-js respectively).

This will also affect the NPM package which we will have to change it from @buidlerlabs/hedera-strato-js to @buidlerlabs/hedera-venin-js with version 0.8.1 being the first one in the repo.

Doc references will also have to be updated as well as the doc CNAME from strato.buidlerlabs.com to venin.buidlerlabs.com. Of course, we will maintain a redirect between the old address and the new one. I don't know how things will behave on GitHub, though, if we update the repo name.

I guess we will find out soon.