build: Allow for kata project build

Rework the build system to allow the runtime to be built for either
of the following:

- Clear Containers (`cc-runtime` binary and configuration)
- Kata Containers (`kata-runtime` binary and configuration)

The existing build rules are retained but there are now two new rules:

```
$ make build-kata-system
$ sudo make install-kata-system
```

Two new variables have also been added:

- `KATA_SYSTEM_BUILD`: set to any value to build/install for Kata.
- `SYSTEM_BUILD_TYPE`: build for either Clear Containers (set to `cc`) or
  Kata (set to `kata`).

See `make help` for further details.

Note that configuration files are installed to a project-specific
directory, allowing for systems to be installed for both Kata and Clear
Containers.

Finally, the bash completion and collection scripts have been updated
to work for either project.

Fixes clearcontainers#919, clearcontainers#921.

Signed-off-by: James O. D. Hunt <james.o.hunt@intel.com>

.gitignore

@@ -1,5 +1,13 @@
 /cc-runtime
+/kata-runtime
 /coverage.html
 /config-generated.go
 /data/cc-collect-data.sh
+/data/cc-collect-data.sh.in
+/data/kata-collect-data.sh
+/data/kata-collect-data.sh.in
+/data/completions/bash/cc-runtime
+/data/completions/bash/cc-runtime.in
+/data/completions/bash/kata-runtime
+/data/completions/bash/kata-runtime.in
 /config/configuration.toml