minor tweaks to demos

Signed-off-by: pjs <pjs@alum.mit.edu>

demos/MMk.rb

 #!/usr/bin/env ruby
 
 # expand the $LOAD_PATH to find local library modules until such
-# time as this gets turned into a Ruby Gem.
+# time as SimpleKit gets turned into a Ruby Gem.
 [File.expand_path(File.dirname(__FILE__), '../lib')].each do |new_location|
   $LOAD_PATH.unshift(new_location) unless $LOAD_PATH.include?(new_location)
 end

demos/MyModelArgs.rb

@@ -12,12 +12,12 @@ class MyModel
 
   def init
     @x = 1
-    schedule(:increment, 1.0, 1, 97)
+    schedule(:increment, rand, 1, 97)
   end
 
   def increment(n, c)
     @x += n
-    schedule(:increment, 1.5, @x, c + 1)
+    schedule(:increment, 2.0 * rand, @x, c + 1)
     printf "%f, %f, %c\n", model_time, @x, c
     schedule(:halt, 0.0) if model_time > 10
   end