Display multi-line commit and tag messages (#3096)

src/blenderbim/docs/users/git_support.rst

@@ -73,6 +73,12 @@ are the same as above: green objects are new to the current model, blue
 objects have changed in some way, and (if you have an older revision loaded)
 red objects have been deleted.
 
+Viewing object history
+----------------------
+
+The history of *everything* in the project is tracked in Git, the revision log
+for the currently selected object can be viewed with the BlenderBIM side-bar.
+
 Retrieving Revisions
 --------------------
 
@@ -156,6 +162,12 @@ optional message text.
     Similar to commit messages, tag messages should be 50 characters or less,
     though there is no practical limit.
 
+.. Warning::
+
+    Tags can be deleted locally, but Git is distributed, so if the tag has
+    migrated to a remote repository it will reappear when you fetch changes
+    from that repository.
+
 Remote operations
 -----------------