xplr: add page (#5819)

pages/common/xplr.md

@@ -0,0 +1,12 @@
+# xplr
+
+> Terminal-based file system explorer.
+> More information: <https://github.com/sayanarijit/xplr>.
+
+- Open a directory:
+
+`xplr {{path/to/directory}}`
+
+- Focus on a file:
+
+`xplr {{path/to/file}}`