Add cmake & build-essential to Ubuntu build packages

[KlfJoat]

cmake is not available by default on a minimal installation of Ubuntu. Add it to the list of packages to install to build kcov.

[KlfJoat]

Also add build-essential to clear the following error when running cmake.

CMake Error at CMakeLists.txt:2 (project):
  No CMAKE_CXX_COMPILER could be found.

[SimonKagstrom]

Great, thanks!

[williamdes]

Hi @KlfJoat

Did you know that you can install kcov directly as an Ubuntu package ?
Ref: https://launchpad.net/ubuntu/+source/kcov

[KlfJoat]

Did you know that you can install kcov directly as an Ubuntu package ? Ref: https://launchpad.net/ubuntu/+source/kcov

I did not, because it's not mentioned in the README or INSTALL files. Might be something for y'all to add.

The instructions were still wrong, though, and still required correction.

[williamdes]

Noted, I think it needs a full review and testing