I am now engaged with emacs prelude and find everything nice. But
A lot of flycheck warnings are displayed while editing el file
and syntax coloring is overrided
Warnings like "the first line shoud be of form package --- summary"
How to turn off those warnings?
These are Checkdoc warnings. To disable these, add emacs-lisp-checkdoc to the option flycheck-disabled-checkers, either with the following code in your init file
(with-eval-after-load 'flycheck
(setq-default flycheck-disabled-checkers '(emacs-lisp-checkdoc)))
or via the customize interface with M-x customize-variable RET flycheck-disabled-checkers.