[BUGFIX] .htaccess rewrite rules

this commit fix #20
[FEATURE] use any kind of meta information for sorting, use meta:date for sort by date meta tag. this remove the "date" option.

fix issue #21
[BUGFIX] fix path handling on windows, use DIRECTORY_SEPARATOR to fix path parsing.
refactor: move getFiles to the Utility class, to make it available everywhere
update meta tags for site_title. fix indentation.
update core
update config