(Fminibufferp, Fread_from_minibuffer)

(Fminibufferp, Fread_from_minibuffer)
(Fread_minibuffer, Feval_minibuffer)
(Fread_string, Fread_no_blanks_input)
(Fcompleting_read): Doc fixes.
(syms_of_minibuf): Doc fixes for minibuffer-completion-table and
completion-regexp-list.  Define Qcase_fold_search and staticpro it.
(read_minibuf): Fix initial comment.
(Ftry_completion, Fall_completions, Ftest_completion): Bind
case-fold-serach to the value of completion-ignore-case when
checking completion-regexp-list.
(Fdisplay_completion_list): Make it handle arguments that are
symbols.  Doc fix.