Include rev-list options in git-log manpage.

Replace the "This manual page describes only the most frequently used options."
text with the list of rev-list options in git-log manpage. (The git-diff-tree
options are already included.)

Move these options to a separate file and include it from both
git-rev-list.txt and git-log.txt.

Signed-off-by: Miklos Vajna <vmiklos@frugalware.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-log.txt

@@ -19,14 +19,10 @@ command to control what is shown and how, and options applicable to
 the linkgit:git-diff-tree[1] commands to control how the changes
 each commit introduces are shown.
 
-This manual page describes only the most frequently used options.
-
 
 OPTIONS
 -------
 
-include::pretty-options.txt[]
-
 :git-log: 1
 include::diff-options.txt[]
 
@@ -41,21 +37,6 @@ include::diff-options.txt[]
 	and <until>, see "SPECIFYING REVISIONS" section in
 	linkgit:git-rev-parse[1].
 
---first-parent::
-	Follow only the first parent commit upon seeing a merge
-	commit.  This option can give a better overview when
-	viewing the evolution of a particular topic branch,
-	because merges into a topic branch tend to be only about
-	adjusting to updated upstream from time to time, and
-	this option allows you to ignore the individual commits
-	brought in to your history by such a merge.
-
--g, \--walk-reflogs::
-	Show commits as they were recorded in the reflog. The log contains
-	a record about how the tip of a reference was changed.
-	Cannot be combined with --reverse.
-	See also linkgit:git-reflog[1].
-
 --decorate::
 	Print out the ref names of any commits that are shown.
 
@@ -80,6 +61,8 @@ include::diff-options.txt[]
 	Show only commits that affect the specified paths.
 
 
+include::rev-list-options.txt[]
+
 include::pretty-formats.txt[]
 
 include::diff-generate-patch.txt[]