tt: add page (#10760)

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

pages/common/tt.md

@@ -0,0 +1,20 @@
+# tt
+
+> A terminal based typing test.
+> More information: <https://github.com/lemnos/tt>.
+
+- Start quote mode with the builtin quote list in English:
+
+`tt -quotes {{en}}`
+
+- Produce a test consisting of 50 randomly drawn words in 5 groups of 10 words each:
+
+`tt -n {{10}} -g {{5}}`
+
+- Start a timed test lasting 10 seconds:
+
+`tt -t {{10}}`
+
+- Start `tt` with no theming and showing your WPM as you type:
+
+`tt -showwpm -notheme`