Allow use of %% to escape a percent sign in the eventconf
Description
Some of the eventconf files contain double percent signs (%%) because it was assumed that this would produce a single percent sign in the output. However, the percent signs are simply erased in the output at least back to version 19. We should implement this to make eventconf output more flexible.
Some of the eventconf files contain double percent signs (%%) because it was assumed that this would produce a single percent sign in the output. However, the percent signs are simply erased in the output at least back to version 19. We should implement this to make eventconf output more flexible.