Updated commands in README.md to match with developer docs

[waridrox]

Signed-off-by: waridrox mohdwarid4@gmail.com

The commands to install vcpkg packages were recently updated in the official developer documentation to run FLINT.Example and GCBM build. They should also be updated in the README.md file to address the issue #80.
CC @gmajan

[aornugent]

Hey @waridrox - I think this is fixed on the develop branch, meaning that it'll be fixed next time we do a release. @mfellows - do you think we could/should we set develop as the default branch, so that it's the first thing people see upon arrival?

[aornugent]

Same applies to #65

[mfellows]

Hey all - yes, master is basically a dead branch (I know, it's weird) - develop really is where we do all of our development, so setting that as the default makes sense, and maybe things need to be reorganized in the future... although I'm not totally sure what that would look like.

[mfellows]

Sorry to notice this so late - PRs against master aren't really going to make it into the builds that people are using, as it's quite old code (Mal/Jim can correct me if my info is out of date though).