Log Message:
Updated waf to 1.8.21.

NEW IN WAF 1.8.21
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* Fix for extra lines in windows logs #1715
* Add commit() method to ConfigSet # 1717
* Enable manifest node objects in java #1722
* Identify java tasks more accurately and add build order on non-jar tasks #1725
* Add PlatformToolset ver. to msvs proj template #1729
* Enable Colorgcc for other compilers #1732