some cleanup, BASIC line finding now properly uses stack

src/basic/basic_commands/cmd_list.s

@@ -31,7 +31,7 @@ list_loop:
 	// LIST terminates any running program,
 	// because it has fiddled with the current line pointer.
 	// (Confirmed by testing on a C64)
-	jmp basic_main_loop
+	jmp shell_main_loop
 
 list_more_lines:
 	lda STKEY

src/basic/basic_commands/cmd_load_verify.s

@@ -80,4 +80,4 @@ cmd_load_no_error:
 
 cmd_load_end:
 
-	jmp basic_main_loop
+	jmp shell_main_loop

src/basic/basic_commands/cmd_new.s

@@ -9,4 +9,4 @@ cmd_new:
 
 	// NEW command terminates execution (confirmed on a C64)
 
-	jmp basic_main_loop
+	jmp shell_main_loop

src/basic/basic_commands/cmd_run_goto.s

@@ -18,7 +18,7 @@ cmd_goto:
 	bcs !+
 
 	jsr basic_parse_line_number
-	jsr basic_find_line
+	jsr find_line
 	bcc !+
 	// Line does not exist, so report error
 	jmp do_UNDEFD_STATEMENT_error

src/basic/basic_commands/cmd_stop_end.s

@@ -27,4 +27,4 @@ cmd_stop:
 
 cmd_end:
 
-	jmp basic_main_loop
+	jmp shell_main_loop