allow renames to be discarded

pkg/commands/file.go

@@ -1,5 +1,7 @@
 package commands
 
+import "strings"
+
 // File : A file from git status
 // duplicating this for now
 type File struct {
@@ -14,3 +16,7 @@ type File struct {
 	Type                    string // one of 'file', 'directory', and 'other'
 	ShortStatus             string // e.g. 'AD', ' A', 'M ', '??'
 }
+
+func (f *File) IsRename() bool {
+	return strings.Contains(f.Name, " -> ")
+}