patch 8.0.0296: bracketed paste can only append, not insert

Problem:    Bracketed paste can only append, not insert.
Solution:   When the cursor is in the first column insert the text.
diff --git a/src/normal.c b/src/normal.c
index 7bae34e..3012bf3 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -9079,8 +9079,13 @@
 		    beginline(BL_WHITE|BL_FIX);
 		break;
 
+	    case K_PS:	/* Bracketed paste works like "a"ppend, unless the
+			   cursor is in the first column, then it inserts. */
+		if (curwin->w_cursor.col == 0)
+		    break;
+		/*FALLTHROUGH*/
+
 	    case 'a':	/* "a"ppend is like "i"nsert on the next character. */
-	    case K_PS:	/* bracketed paste works like "a"ppend */
 #ifdef FEAT_VIRTUALEDIT
 		/* increment coladd when in virtual space, increment the
 		 * column otherwise, also to append after an unprintable char */