* exclude build artifacts from git
* build: simplify building by using src-d/ci
* bench: simplify&fix shell runners
* build: simplify benchmarks* targets
* test: remove dependency on single test suite
* doc: rel image link + linguist cli difference highlight
* suggestions from code review
* bench: add fail fast to all shell runners
Signed-off-by: Alexander Bezzubov <bzz@apache.org>
