diff: make struct diff_flags members lowercase

Now that the flags stored in struct diff_flags are being accessed
directly and not through macros, change all struct members from being
uppercase to lowercase.
This conversion is done using the following semantic patch:

	@@
	expression E;
	@@
	- E.RECURSIVE
	+ E.recursive

	@@
	expression E;
	@@
	- E.TREE_IN_RECURSIVE
	+ E.tree_in_recursive

	@@
	expression E;
	@@
	- E.BINARY
	+ E.binary

	@@
	expression E;
	@@
	- E.TEXT
	+ E.text

	@@
	expression E;
	@@
	- E.FULL_INDEX
	+ E.full_index

	@@
	expression E;
	@@
	- E.SILENT_ON_REMOVE
	+ E.silent_on_remove

	@@
	expression E;
	@@
	- E.FIND_COPIES_HARDER
	+ E.find_copies_harder

	@@
	expression E;
	@@
	- E.FOLLOW_RENAMES
	+ E.follow_renames

	@@
	expression E;
	@@
	- E.RENAME_EMPTY
	+ E.rename_empty

	@@
	expression E;
	@@
	- E.HAS_CHANGES
	+ E.has_changes

	@@
	expression E;
	@@
	- E.QUICK
	+ E.quick

	@@
	expression E;
	@@
	- E.NO_INDEX
	+ E.no_index

	@@
	expression E;
	@@
	- E.ALLOW_EXTERNAL
	+ E.allow_external

	@@
	expression E;
	@@
	- E.EXIT_WITH_STATUS
	+ E.exit_with_status

	@@
	expression E;
	@@
	- E.REVERSE_DIFF
	+ E.reverse_diff

	@@
	expression E;
	@@
	- E.CHECK_FAILED
	+ E.check_failed

	@@
	expression E;
	@@
	- E.RELATIVE_NAME
	+ E.relative_name

	@@
	expression E;
	@@
	- E.IGNORE_SUBMODULES
	+ E.ignore_submodules

	@@
	expression E;
	@@
	- E.DIRSTAT_CUMULATIVE
	+ E.dirstat_cumulative

	@@
	expression E;
	@@
	- E.DIRSTAT_BY_FILE
	+ E.dirstat_by_file

	@@
	expression E;
	@@
	- E.ALLOW_TEXTCONV
	+ E.allow_textconv

	@@
	expression E;
	@@
	- E.TEXTCONV_SET_VIA_CMDLINE
	+ E.textconv_set_via_cmdline

	@@
	expression E;
	@@
	- E.DIFF_FROM_CONTENTS
	+ E.diff_from_contents

	@@
	expression E;
	@@
	- E.DIRTY_SUBMODULES
	+ E.dirty_submodules

	@@
	expression E;
	@@
	- E.IGNORE_UNTRACKED_IN_SUBMODULES
	+ E.ignore_untracked_in_submodules

	@@
	expression E;
	@@
	- E.IGNORE_DIRTY_SUBMODULES
	+ E.ignore_dirty_submodules

	@@
	expression E;
	@@
	- E.OVERRIDE_SUBMODULE_CONFIG
	+ E.override_submodule_config

	@@
	expression E;
	@@
	- E.DIRSTAT_BY_LINE
	+ E.dirstat_by_line

	@@
	expression E;
	@@
	- E.FUNCCONTEXT
	+ E.funccontext

	@@
	expression E;
	@@
	- E.PICKAXE_IGNORE_CASE
	+ E.pickaxe_ignore_case

	@@
	expression E;
	@@
	- E.DEFAULT_FOLLOW_RENAMES
	+ E.default_follow_renames

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/combine-diff.c b/combine-diff.c
index 5a3a8b4..23f3d25 100644
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -898,7 +898,7 @@ static void show_combined_header(struct combine_diff_path *elem,
 				 int show_file_header)
 {
 	struct diff_options *opt = &rev->diffopt;
-	int abbrev = opt->flags.FULL_INDEX ? GIT_SHA1_HEXSZ : DEFAULT_ABBREV;
+	int abbrev = opt->flags.full_index ? GIT_SHA1_HEXSZ : DEFAULT_ABBREV;
 	const char *a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
 	const char *b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
 	const char *c_meta = diff_get_color_opt(opt, DIFF_METAINFO);
@@ -987,7 +987,7 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
 	userdiff = userdiff_find_by_path(elem->path);
 	if (!userdiff)
 		userdiff = userdiff_find_by_name("default");
-	if (opt->flags.ALLOW_TEXTCONV)
+	if (opt->flags.allow_textconv)
 		textconv = userdiff_get_textconv(userdiff);
 
 	/* Read the result of merge first */
@@ -1413,8 +1413,8 @@ void diff_tree_combined(const struct object_id *oid,
 
 	diffopts = *opt;
 	copy_pathspec(&diffopts.pathspec, &opt->pathspec);
-	diffopts.flags.RECURSIVE = 1;
-	diffopts.flags.ALLOW_EXTERNAL = 0;
+	diffopts.flags.recursive = 1;
+	diffopts.flags.allow_external = 0;
 
 	/* find set of paths that everybody touches
 	 *
@@ -1435,7 +1435,7 @@ void diff_tree_combined(const struct object_id *oid,
 	 * NOTE please keep this semantically in sync with diffcore_std()
 	 */
 	need_generic_pathscan = opt->skip_stat_unmatch	||
-			opt->flags.FOLLOW_RENAMES	||
+			opt->flags.follow_renames	||
 			opt->break_opt != -1	||
 			opt->detect_rename	||
 			opt->pickaxe		||