obj_pledge_peace scaffold
No i18n yet. Haven't viewed whether all the effects are showed
properly by the UI either. Needs an all-CBs sweep (ugh).
Fix file permissions
Pass over all [relevant] CBs to disable during peace pledge
Added catch-all abort condition to peace ambition
Updated catch-all abort cases
Placeholder obj_pledge_peace icon
Pledge Peace for 15 Years ambition effectively ready
Merge pull request #113 from zijistark/pledge_peace

Pledge Peace for 15 Years, a strategic effect ambition