Add a new UA to UserAgent
Update xsd file

Rename ModeConfig to WorkConfig;
Add WorkFolder attribute
Update ModeConfig class

Rename it to WorkConfig
Add WorkFolder attribute
Fix a bug in FileTools

We should consume entity anyway after download or sometims issues occur.
Fix a bug in StringTools class

Return null if the input string is null,
simplize the code,
change several variables' name
UPdate CoreData class

Simplized the code.
Rename ModeConfig to WorkConfig