Handle events in text interpolation; capture text events in choice lines; improve test script

test/tests/text line interpolation with event flush.lua

@@ -0,0 +1,50 @@
+local _={}
+_[20]={1}
+_[19]={}
+_[18]={1}
+_[17]={}
+_[16]={text=" to move.",tags=_[19]}
+_[15]={text=" joystick",tags=_[19]}
+_[14]={text="left",tags=_[20]}
+_[13]={text="Use ",tags=_[19]}
+_[12]={text=" to jump.",tags=_[17]}
+_[11]={text="A",tags=_[18]}
+_[10]={text="Press ",tags=_[17]}
+_[9]={_[15],_[16]}
+_[8]={_[13],_[14]}
+_[7]={_[12]}
+_[6]={_[10],_[11]}
+_[5]={"return"}
+_[4]={"text",_[9]}
+_[3]={"text",_[8]}
+_[2]={"text",_[7]}
+_[1]={"text",_[6]}
+return {_[1],_[2],_[3],_[4],_[5]}
+--[[
+{ "text", { {
+      tags = {},
+      text = "Press "
+    }, {
+      tags = { 1 },
+      text = "A"
+    } } }
+{ "text", { {
+      tags = {},
+      text = " to jump."
+    } } }
+{ "text", { {
+      tags = {},
+      text = "Use "
+    }, {
+      tags = { 1 },
+      text = "left"
+    } } }
+{ "text", { {
+      tags = <1>{},
+      text = " joystick"
+    }, {
+      tags = <table 1>,
+      text = " to move."
+    } } }
+{ "return" }
+]]--