azure: Prepare configuration for 4-core machines

[alexcrichton]

This commit updates some of our assorted Azure/CI configuration to
prepare for some 4-core machines coming online. We're still in the
process of performance testing them to get final numbers, but some
changes are worth landing ahead of this. The updates here are:

• Use C:/ instead of D:/ for submodule checkout since it should have
  plenty of space and the 4-core machines won't have D:/

• Update lzma-sys to 0.1.14 which has support for VS2019, where 0.1.10
  doesn't.

• Update src/ci/docker/run.sh to work when it itself is running inside
  of a docker container (see the comment in the file for more info)

• Print step timings on the try branch in addition to the auto
  branch in. The logs there should be seen by similarly many humans (not
  many) and can be useful for performance analysis after a try build
  runs.

• Install the WIX and InnoSetup tools manually on Windows instead of
  relying on pre-installed copies on the VM. This gives us more control
  over what's being used on the Azure cloud right now (we control the
  version) and in the 4-core machines these won't be pre-installed. Note
  that on AppVeyor we actually already were installing InnoSetup, we
  just didn't carry that over on Azure!

[rust-highfive]

r? @pietroalbini

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[alexcrichton]

r? @pietroalbini

[pietroalbini]

@bors r+ rollup=never

[bors]

📌 Commit 5cd66f50e3c90b80d89a2023942ef77f688fb50a has been approved by pietroalbini

[bors]

🔒 Merge conflict

This pull request and the master branch diverged in a way that cannot be automatically merged. Please rebase on top of the latest master branch, and let the reviewer approve again.

How do I rebase?

Assuming self is your fork and upstream is this repository, you can resolve the conflict following these steps:

1. git checkout azure-update (switch to your branch)
2. git fetch upstream master (retrieve the latest master)
3. git rebase upstream/master -p (rebase on top of it)
4. Follow the on-screen instruction to resolve conflicts (check git status if you got lost).
5. git push self azure-update --force-with-lease (update this PR)

You may also read Git Rebasing to Resolve Conflicts by Drew Blessing for a short tutorial.

Please avoid the "Resolve conflicts" button on GitHub. It uses git merge instead of git rebase which makes the PR commit history more difficult to read.

Sometimes step 4 will complete without asking for resolution. This is usually due to difference between how Cargo.lock conflict is handled during merge and rebase. This is normal, and you should still perform step 5 to update this PR.

Error message

warning: Cannot merge binary files: Cargo.lock (HEAD vs. heads/homu-tmp)
Auto-merging src/ci/run.sh
Auto-merging src/ci/docker/run.sh
Auto-merging Cargo.lock
CONFLICT (content): Merge conflict in Cargo.lock
Automatic merge failed; fix conflicts and then commit the result.

[alexcrichton]

@bors: r=pietroalbini

[bors]

📌 Commit 9b4f6de has been approved by pietroalbini

[bors]

⌛ Testing commit 9b4f6de with merge e3cebcb...

[bors]

☀️ Test successful - checks-azure
Approved by: pietroalbini
Pushing e3cebcb to master...