patch 8.0.0210: no support for bracketed paste

Problem:    Vim does not support bracketed paste, as implemented by xterm and
            other terminals.
Solution:   Add t_BE, t_BD, t_PS and t_PE.
diff --git a/src/getchar.c b/src/getchar.c
index 9adeafa..9583d9a 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -1817,6 +1817,12 @@
     {
 	c = safe_vgetc();
     } while (c == K_IGNORE || c == K_VER_SCROLLBAR || c == K_HOR_SCROLLBAR);
+
+    if (c == K_PS)
+	/* Only handle the first pasted character.  Drop the rest, since we
+	 * don't know what to do with it. */
+	c = bracketed_paste(PASTE_ONE_CHAR, FALSE, NULL);
+
     return c;
 }
 
@@ -1906,7 +1912,7 @@
 }
 
 /*
- * get a character:
+ * Get a character:
  * 1. from the stuffbuffer
  *	This is used for abbreviated commands like "D" -> "d$".
  *	Also used to redo a command for ".".