Replace custom ibuffer code with ibuffer-project - Remove custom ibuffer major-mode grouping functions using obsolete flet - Add ibuffer-project package for automatic project-based buffer grouping - Simplify configuration from ~25 lines to ~6 lines

syntax: regexp
^url\/
^elpa\/
^eshell\/
^smex-items$
\.elc$
\.mc-lists\.el$
\.DS_Store$
session\..*$
ac-comphist\.dat$
^projectile-bookmarks\.eld$
~$
\#.*\#$