[PROTON-1301] add pn_condition_format for formatted descriptions

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: proton-0.14.0
• Fix Version/s: proton-0.15.0
• Component/s: proton-c
• Assignee: Alan Conway
• Reporter: Alan Conway
• Created: 13/Sep/16 14:47
• Updated: 08/Feb/17 19:06
• Resolved: 13/Sep/16 21:50

Description

Add pn_condition_format/vformat similar to pn_error_format/vformat so a condition description can be set using a printf-style format string.