phabricator: add a config knob to import in the secret phase
For my use anyway, it's better to have a config knob that's always set than to
try to remember a switch. But we can add a tristate switch if desired.
Differential Revision: https://phab.mercurial-scm.org/D8137
{
"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"
}