Merge pull request libgit2#3944 from mhagger/diff-indent-heuristic

Implement a diff indent heuristic

Author: carlosmn

src/xdiff/xdiff.h

@@ -43,6 +43,8 @@ extern "C" {
 
 #define XDF_IGNORE_BLANK_LINES (1 << 7)
 
+#define XDF_INDENT_HEURISTIC (1 << 8)
+
 #define XDL_EMIT_FUNCNAMES (1 << 0)
 #define XDL_EMIT_COMMON (1 << 1)
 #define XDL_EMIT_FUNCCONTEXT (1 << 2)