atomic.bootstrap: improve quoting
atomic.bootstrap: improve quoting

Quote a whole lot of unsafe shell variable expansions.  Thanks to Martin
for the poke to fix these.

mvollmer/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,deryni/cockpit,cockpituous/cockpit,garrett/cockpit,cockpituous/cockpit,cockpituous/cockpit,martinpitt/cockpit,garrett/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,martinpitt/cockpit,cockpituous/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,mvollmer/cockpit,mvollmer/cockpit,deryni/cockpit,garrett/cockpit,cockpit-project/cockpit,deryni/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,garrett/cockpit,garrett/cockpit,cockpituous/cockpit,deryni/cockpit,deryni/cockpit,mvollmer/cockpit,mvollmer/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,deryni/cockpit,martinpitt/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,deryni/cockpit,cockpituous/cockpit