Bugfix: default case insensitive filters for programmatic and Spring / Spring Boot configurations

[lprimak]

This is a bug fix. During programmatic instantiation, or with Spring / Spring Boot without shiro.ini, the default behavior remained case-sensitive matching, which is incorrect and doesn't match the documentation for Shiro 3.x

Finder Credit: 0xCc.zhang

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[steinarb]

LGTM!