update function generateRandomChar

update function generateRandomChar
Merge https://github.com/dgq2010/niot

Conflicts:
	source/niot/WebRoot/WEB-INF/classes/cn/niot/controller/RecoAction.class
	source/niot/WebRoot/WEB-INF/classes/cn/unitTest/RuleFuncTest.class
	source/niot/src/cn/unitTest/RuleFuncTest.java