Remove hard coded single quotes in arc feature
Remove hard coded single quotes in arc feature

Summary:
Single quotes aren't valid in the windows cmd prompt, so arc feature
didn't work in mercurial when it got to this line.

I have no idea why %C was used before.  Nothing in that string should be
broken by the escaping.

Test Plan:
Ran arc feature --trace on my mac. Verified the command was escaped correctly
and the correct feature results were printed.

I don't have a windows machine to try it on, but the builtin escaping should
now account for windows machines.

Reviewers: epriestley

Reviewed By: epriestley

CC: sid0, aran, Korvin

Differential Revision: https://secure.phabricator.com/D6637

fivestars/arcanist,fivestars/arcanist,Symplicity/arcanist,uber/arcanist,alexmv/arcanist,memsql/arcanist,phacility/arcanist,PageUpPeopleOrg/arcanist-patches,hach-que/arcanist,alexmv/arcanist,Symplicity/arcanist,aik099/arcanist,sneakpeeq/arcanist,julkiewicz/arcanist,PageUpPeopleOrg/arcanist-patches,dguo-coursera/arcanist,wxstars/arcanist,zhihu/arcanist,aik099/arcanist,eSpark/arcanist,jra3/arcanist,wharris/arcanist,wxstars/arcanist,phacility/arcanist,codelabs-ch/arcanist,r4nt/arcanist,jra3/arcanist,r4nt/arcanist,wharris/arcanist,phacility/arcanist,wikimedia/phabricator-arcanist,wharris/arcanist,dguo-coursera/arcanist,wharris/arcanist,jra3/arcanist,wxstars/arcanist,chundongwang/arcanist,zhihu/arcanist,Symplicity/arcanist,sneakpeeq/arcanist,zhihu/arcanist,fivestars/arcanist,dguo-coursera/arcanist,memsql/arcanist,aik099/arcanist,alexmv/arcanist,hach-que/arcanist,kevinseelbach/arcanist,dguo-coursera/arcanist,sneakpeeq/arcanist,hach-que/arcanist,calblueprint/arcanist,calblueprint/arcanist,r4nt/arcanist,kevinseelbach/arcanist,memsql/arcanist,julkiewicz/arcanist,codelabs-ch/arcanist,Khan/arcanist,phacility/arcanist,zhihu/arcanist,KieranHayes/arcanist,folsom-labs/arcanist,jra3/arcanist,coursera/arcanist,fivestars/arcanist,kevinseelbach/arcanist,uber/arcanist,PageUpPeopleOrg/arcanist-patches,uber/arcanist,memsql/arcanist,chundongwang/arcanist,alexmv/arcanist,calblueprint/arcanist,haskell-infra/arcanist,calblueprint/arcanist,coursera/arcanist,KieranHayes/arcanist,Khan/arcanist,phacility/arcanist,Khan/arcanist,chundongwang/arcanist,codelabs-ch/arcanist,eSpark/arcanist,sneakpeeq/arcanist,chundongwang/arcanist,aik099/arcanist,codelabs-ch/arcanist,uber/arcanist,wikimedia/phabricator-arcanist,wikimedia/phabricator-arcanist,haskell-infra/arcanist,wxstars/arcanist,eSpark/arcanist,KieranHayes/arcanist,julkiewicz/arcanist,r4nt/arcanist,coursera/arcanist,julkiewicz/arcanist,folsom-labs/arcanist,wikimedia/phabricator-arcanist,eSpark/arcanist,coursera/arcanist,folsom-labs/arcanist,kevinseelbach/arcanist,codelabs-ch/arcanist,KieranHayes/arcanist,folsom-labs/arcanist,Symplicity/arcanist,haskell-infra/arcanist,Khan/arcanist,hach-que/arcanist,PageUpPeopleOrg/arcanist-patches,haskell-infra/arcanist