Renaming the project to Minefast

[charlyoleg2]

The word 'manifest' is used for a long time in software. Hence this term is not convenient for the search engine. Having a more exotic name like 'minefast' would make the project more google-able.

[brunobuddy]

Closing this out. It's from Manifest's old backend-as-a-service days, which we don't work on anymore since the pivot. See #742 for where things are now.