Full system instrumentation, excluding regions of code

The main new feature of this version is full-system instrumentation. With this, kcov can instrument binaries for an embedded system, which together with a daemon can collect coverage from a target system automatically (i.e., without changing the command line).

The other major feature is the ability to filter out source lines from files (kcov can filter out entire files since before). This is useful e.g., for Rust where test code is often bundled with the implementation.

Apart from these features, there are a number of bug fixes and smaller feature improvements.