change style loading strategy
extracted default styles to rubygems
Revert "extracted default styles to rubygems"

This reverts commit be225cc4dd872218424b498522cd88ac37b2c0aa.
extracted additional styles
rename
remove external gem dependency
allow array args into conf.style
rename
Merge pull request #376 from tdiary/style-gem

[WIP] tDiary の各種スタイルを gem に分離した