cmd/bent: refactor common benchmark info into "suites.toml"; add versions

Common fields in benchmark*toml were a headache, especially w/
the addition of versions.  This was a big improvement, all the
common info (build flags, gc env, etc) can appear there.

Also added interpretation of "temporary pattern" for configured
"RunDir" for tests that expect to run in a writeable directory
(and also w/o testdata, which seems to be the case for at least
one bench).

Also sorted through benchmarks to get most (all?) running in
the "all" case.

Change-Id: Id80695c11466ec86810107c1a4acefcde991bff9
Reviewed-on: https://go-review.googlesource.com/c/benchmarks/+/355749
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
4 files changed