contrib/asv.conf.json

bundlespec: merge the contentopts and params dictionnary

They are content using the same keys. Using differents object for access open
the gates for confusion in the code using them (this is already the case). So we
start fusing their usages to make the parameters more useful.

More work will be needed to make them really useful, but the first step is
here: not throwing the value away.

However this is still not making the previously introduced test useful because
currently, the default config value overwrite the one from the bundlespec. We
will fix this in the coming changesets.

{
    "version": 1,
    "project": "mercurial",
    "project_url": "https://mercurial-scm.org/",
    "repo": "..",
    "branches": ["default", "stable"],
    "environment_type": "virtualenv",
    "show_commit_url": "https://www.mercurial-scm.org/repo/hg/rev/",
    "benchmark_dir": "benchmarks",
    "env_dir": "../.asv/env",
    "results_dir": "../.asv/results",
    "html_dir": "../.asv/html"
}