Replacing hostile with first-party solution

[williamlark]

We used hostile to modify the users hosts entries in the sku setup-hosts command. It's been useful, but it contains a CLI which sku does not need. Since sku only uses hostile for adding entries to hosts and doesn't need all of its more complex logic, we can roll our own implementation pretty simply while fixing a few quirks.

What changed

• We now only appends lines to the hosts file. It does not change existing lines, comments, tabs or inline comments. hostile rewrote every entry line in the file.
• No longer replace the IP address on an existing line for an app host. If the hosts file maps an app host to a different IP address of the same version (IPv4 or IPv6), setup-hosts shows a warning. The warning is needed since the existing line may take precedence over the line that sku appends and I don't want to silently overwrite it.
• Only log lines that are added, rather than saying everything was added every time. If the file already contains all app hosts, it logs a message that says so.
• sku start now waits for checkHosts to finish before it continues.
• checkHosts finds hosts on lines that contain more than one host name, for example 127.0.0.1 a.test b.test. Before this change, checkHosts showed a false "not configured" warning for these hosts, unless the host name ended in .localhost.

Setting up new hosts

All entries exist

Conflicting IPs

[changeset-bot]

🦋 Changeset detected

Latest commit: 535987b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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sku	Patch

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[askoufis]

Neat! Just one non-blocking suggestion.