Add ticker_geom_t.

This lets a single ticker object drive events across a large number of different
tick streams while sharing state.

src/ticker.py

@@ -0,0 +1,15 @@
+#!/usr/bin/env python3
+
+import math
+
+# Must match TICKER_GEOM_NBITS
+lg_table_size = 6
+table_size = 2**lg_table_size
+byte_max = 255
+mul = math.floor(-byte_max/math.log(1 / table_size))
+values = [round(-mul * math.log(i / table_size))
+	for i in range(1, table_size+1)]
+print("mul =", mul)
+print("values:")
+for i in range(table_size // 8):
+	print(", ".join((str(x) for x in values[i*8 : i*8 + 8])))