Add building section for Linux to README.md

[dolohow]

No description provided.

[coveralls]

Coverage remained the same when pulling 7c312ec on dolohow:master into dd83e58 on zsiciarz:master.

[ulikoehler]

@dolohow I think it should be cmake . instead of cmake CMakeLists.txt
Also, it would be gread if you'd add a paragraph like this:

In order to build the test suite, use

make aquila_test

After that, you can run it using

./tests/aquila_test

[KilroyWasHere-cs-j]

I currently have issues for building for fedora and it would be helpful to have better documentation.

[ulikoehler]

Wow, has it really been 7 years since I posted this :-?
It would certainly be good if this could be merged.