add test
ignore args of Parameters.new()
remove path_param

NOTE: current implementation of path_param is buggy; "/" is added at front of path string.
It should be fixed and "/" should be removed :-/
remove unused method: Parameters.get_page_metric and Parameters.const_get_safe
ReVIEW::Book::Base: stop forwarding to ReVIEW::Parameters and use ReVIEW::Configure
remove ReVIEW::Book::Parameters
Remove / from paths
Fix tests
Fix path
Merge pull request #326 from kmuto/remove-parameters

remove ReVIEW::Book::Parameters
add test
fix error `read_POSTDEF': undefined method `postdef' for nil:NilClass (NoMethodError)
remove unused method Chapter.for_stdin and Chapter.for_path
add default value for @config
when argument of read_FILE is dir, return ""
`:UTF-8` is not Symbol literal; use String
remove ReVIEW.book
fix tests
remove another ReVIEW.book
rubocop: disable some warnings of style

now we have too many warnings :-(