(defgroup grep): Doc fix.

(defgroup grep): Doc fix.
(grep-auto-highlight): Remove.
(grep-template): New defcustom.
(grep-find-template): Rename from grep-tree-template.
(grep-files-aliases): Rename from grep-tree-files-aliases.
Remove "all" alias, add "l" alias.
(grep-tree-ignore-case, grep-tree-ignore-CVS-directories): Remove.
(grep-find-ignored-directories): New defcustom to replace
grep-tree-ignore-CVS-directories, to facilitate ignoring
subdirectories for multiple version control systems.
(grep-mode-map): Add Recursive grep item to GREP menu.
(grep-regexp-history, grep-files-history): New defvars.
(grep-probe): New helper function.
(grep-compute-defaults): Use it to simplify code.
Adapt to name changes.
Use `.' as base in grep-find-template rather than <D>.
(grep): Remove superfluous highlight-regexp arg.  Fix doc.
Call grep-compute-defaults unconditionally.
(grep-expand-keywords): New defconst.
(grep-expand-template): Rename from grep-expand-command-macros.
Simplify via grep-expand-keywords.  Look at case-fold-search instead
of grep-tree-ignore-case to add -i option.
Bind case-fold-search to nil while matching keywords.
(grep-tree-last-regexp, grep-tree-last-files): Remove.
(grep-read-regexp, grep-read-files): New helper functions.
(rgrep): Rename from grep-tree.	 Rework to use proper histories.
Adapt to changes in defcustoms and functions above.
(lgrep): New command, as grep, but using same interactive api as rgrep.