PLAT-6398 - Integrate user management with components

Provide ability to handle prefixed permissions
PLAT-6398 - Integrate user management with components

Fixup based on PR comments
PLAT-6398 FixPR - Integrate user management with components
PLAT-6398 FixPR - Integrate user management with components

Use correct exception type
Merge pull request #19 from OpenGamma/topic/plat-6398

PLAT-6398 - Extend Shiro permission support