Merge from release:

When processing value multitoken options, don't eat futher options. 
Fixes #469. 


[SVN r52210]

libs/program_options

@@ -1 +1 @@
-Subproject commit 454c878389c44a9252fb0b53fcec3b5ec461113b
+Subproject commit 600a8aa105aa10cb76e711df7122803add0daaab