init.el: replace default case change function to auto change the comma/dot at front of it.
init.el: restore useful iy-go-to-char configuration, add comments about yasnippet
snippets: mv file like "abc def" to "abc_def", remove blank line at the end of some files
init.el: make delete-trailing-whitespace safer, delete indent-guide, it will stuck Emacs in many situations, such as with yafolding
init.el: keep C-o to open-newline(default)(in S-return), tweak ace-jump-mode
elpa: add base-16 family themes
init.el: tweak M-S-return to make it work even if cursor is at the top of a file
init.el: disable sub/superscript option in org-export
elpa: add base-16 family themes, restore iy-go-to-char package, updates