GROOVY-6457 Update eachFileMatch to behave like eachFile

GROOVY-6457

[File.eachFileMatch](http://groovy.codehaus.org/groovy-jdk/java/io/File.html#eachFileMatch%28groovy.io.FileType,%20java.lang.Object,%20groovy.lang.Closure%29) is very similar to [File.eachFile](http://groovy.codehaus.org/groovy-jdk/java/io/File.html#eachFile%28groovy.io.FileType,%20groovy.lang.Closure%29) but it has one subtle difference: it doesn't shortcircuit on FileTypes.ANY. This means that they return different results for directory entries that aren't files or directories and that it can be significantly slower due to Java needing to invoke a ```stat()``` system call for every entry.

See [GROOVY-6457](http://jira.codehaus.org/browse/GROOVY-6457) for details and demos.