Add YARD documentation

(cherry picked from commit 2fafe0b)

Author: mhashizume

ext/windows/service/daemon.rb

@@ -159,6 +159,10 @@ def report_windows_event(type,id,message)
     end
   end
 
+  # Parses runinterval.
+  #
+  # @param puppet_path [String] The file path for the Puppet executable.
+  # @return runinterval [Integer] How often to do a Puppet run, in seconds.
   def parse_runinterval(puppet_path)
     begin
       runinterval = %x{ #{puppet_path} config --section agent --log_level notice print runinterval }.to_i