[jtnelson]

Summary

A release branch or a Renovate branch of process-watcher builds the plain
version that only master should, such as 1.1.0, and Gradle publishes it to
open-source, the releases repository. A feature branch publishes there too.
The published version also loses every digit of a branch's name, so
feature/GH-60-fix publishes as 1.1.0-GH--FIX, and branches that differ only
in their issue number publish the same version.

This adopts the shared version tool, the one set of version rules for every
Cinchapi repo, from cinchapi/cinchapi-agent-skills#70. Part of
cinchapi/cinchapi-agent-skills#67.

Behavior

version.sh is a copy of the shared tool at the pinned commit of .agents, and
every skills pull refreshes it. Gradle and tools/release call it as before.

Branch	Published version	Repository
master	1.1.0	open-source
release/*	1.1.0-rc<n>	open-source-snapshots
develop	1.1.0-SNAPSHOT	open-source-snapshots
any other, such as feature/GH-60-fix	1.1.0-FEATURE-GH-60-FIX	open-source-snapshots

Only a plain X.Y.Z goes to the releases repository. A release candidate carries
its build number as -rc<n>, so each candidate is a distinct version.

version.sh X.Y.Z, which tools/release runs, also sets the version in any
build.gradle's pom.version line through .on-version-set.sh, as the old
setter did.

In CI, where CONTAINER_BUILD is set, the build number is the epoch second, as
in every other repo, rather than a count that restarts with each checkout.