Refine CI

[Hoverbear]

Use cross platform CI. Linux Stable is red ATM due to a clippy problem, don't block merge for that.

[brson]

I'd like to know the answer to my question about 'before_script' but otherwise LGTM!

[brson]

It looks like there's a feature that needs to be removed now that clippy is stable:

error[E0554]: #![feature] may not be used on the stable release channel
   --> /home/travis/.cargo/registry/src/github.com-1ecc6299db9ec823/raft-0.4.0/src/lib.rs:264:39
    |
264 | #![cfg_attr(feature = "cargo-clippy", feature(tool_lints))]
    |                                       ^^^^^^^^^^^^^^^^^^^

Oh, this is an error in the raft crate! Maybe the stabilization of "cargo-clippy" broke raft on stable?

[brson]

It looks like travis itself is timing out on windows while backing up the cargo cache.

It also timed out on linux but in a way that didn't cause an error.

Maybe for now you could remove the cache: cargo line.

[brson]

I went ahead and pushed a commit to remove the cargo build cache from travis, see how that affects the windows build.

[Hoverbear]

Rebased with signoff because somehow I forgot. 🙈

[brson]

There are a few 'integration' test files that look unrelated to the PR, but I assume you know what you're doing.

[Hoverbear]

@brson Let me take a look at them...

[Hoverbear]

@brson Yes we moved the tests that require a live TiKV to behind a feature flag. Hence the change.