git-diff-index, git-diff-tree: add page (#11234)

* git-diff-index, git-diff-tree: add page

---------

Co-authored-by: Sebastiaan Speck <12570668+sebastiaanspeck@users.noreply.github.com>
Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

pages/common/git-diff-tree.md

@@ -0,0 +1,20 @@
+# git diff-tree
+
+> Compares the content and mode of blobs found via two tree objects.
+> More information: <https://git-scm.com/docs/git-diff-tree>.
+
+- Compare two tree objects:
+
+`git diff-tree {{tree-ish1}} {{tree-ish2}}`
+
+- Show changes between two specific commits:
+
+`git diff-tree -r {{commit1}} {{commit2}}`
+
+- Display changes in patch format:
+
+`git diff-tree -p {{tree-ish1}} {{tree-ish2}}`
+
+- Filter changes by a specific path:
+
+`git diff-tree {{tree-ish1}} {{tree-ish2}} -- {{path/to/file_or_directory}}`