haproxy_ctld_daemon.rb: Fix backtrace option

The haproxy_ctld_daemon.rb script in the haproxy cartridge had a typo:
':backgrace' instead of ':backtrace'.

This typo appears to have been present since haproxy_ctld_daemon.rb was
introduced in commit ee8cebbe1adb351a3b80ca3fda4f047aee8fac1b.
Card 57 - provide simple visual branding to the admin console
Card 57 - review feedback
Card 57 - update Gemfiles to use rubygems sass-twitter-bootstrap
Card 57 - make admin console header responsive
Card 57 - make admin console pages responsive
Adding Fedora vs RHEL cases for idler.
Ruby 2.0 in F19 runs as ruby-mri vs ruby in RHEL
<admin-console> broker proxy RPP change + filling in README
<admin-console> adding some configuration options
Card 57 - make histograms responsive
<admin-console> revising packaging
For consistency, rest api response must display 'delete' instead 'destroy' for user/domain/app
Minor tweaks and fixes
Add cartridge and app developers guides
Use service script instead of SIGUSR to reload mcollective
Restructure index; correct missing CSS classes
Merge pull request #3165 from nhr/updates

Add cartridge developer's guide; index refactor
<oo-idler-stats> Bug 977293 - Fix get_app_type for v2 carts

https://bugzilla.redhat.com/show_bug.cgi?id=977293

get_app_type was trying to match against v1 cartridge paths, updated to
test for correct v2 paths.
handle rpms with gem as Source0
Workaround for F19 mcollective issue where it goes into inf. loop and 100% cpu usage.
Using mcollctive restart instead of mcollective reload.