small_vector should be feature-wise compatible with std::vector<>,
let's add operator<=> for it.
also, there is not needd to define operator!=() explicitly, C++20
define this for us if operator==() is defined, so let's drop it.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closes#13032
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
1. Move tests to test (using singular seems to be a convention
in the rest of the code base)
2. Move boost tests to test/boost, other
(non-boost) unit tests to test/unit, tests which are
expected to be run manually to test/manual.
Update configure.py and test.py with new paths to tests.
