Extend tempo limit from 20 to 30

For mods like tickratechanger, the tempo can go higher than 20. Programs could read the NBS file and translate it to tickrate change commands for the mod.

Author: ShinkoNet

scripts/control_draw/control_draw.gml

@@ -966,7 +966,7 @@ if (a && window = 0) {
 if (window = w_dragtempo) {
     curs = cr_size_ns
     tempodrag += 0.25 * (mouse_yprev - mouse_y) / 3
-    tempodrag = median(0.25, tempodrag, 20)
+    tempodrag = median(0.25, tempodrag, 30)
     a = tempo
     tempo = floor(tempodrag * 4) / 4
     if (a != tempo) changed = 1

scripts/load_song/load_song.gml

@@ -48,7 +48,7 @@ if (file_ext = ".nbs") {
     // SONG DESCRIPTION
     song_desc = buffer_read_string_int()
     // TEMPO
-    tempo = median(0.25, floor((buffer_read_short() / 100) * 4) / 4, 20)
+    tempo = median(0.25, floor((buffer_read_short() / 100) * 4) / 4, 30)
     // AUTOSAVE
     a = buffer_read_byte()
     autosave = median(0, a, 1)