patch 8.1.1513: all popup functionality is in functions, except :popupclear

Problem:    All popup functionality is in functions, except :popupclear.
Solution:   Add popup_clear() for consistency.  Also rename sound_stopall() to
            sound_clear().
diff --git a/src/ex_cmdidxs.h b/src/ex_cmdidxs.h
index 2aae4b6..0103a17 100644
--- a/src/ex_cmdidxs.h
+++ b/src/ex_cmdidxs.h
@@ -21,16 +21,16 @@
   /* n */ 285,
   /* o */ 305,
   /* p */ 317,
-  /* q */ 357,
-  /* r */ 360,
-  /* s */ 380,
-  /* t */ 448,
-  /* u */ 493,
-  /* v */ 504,
-  /* w */ 522,
-  /* x */ 536,
-  /* y */ 546,
-  /* z */ 547
+  /* q */ 356,
+  /* r */ 359,
+  /* s */ 379,
+  /* t */ 447,
+  /* u */ 492,
+  /* v */ 503,
+  /* w */ 521,
+  /* x */ 535,
+  /* y */ 545,
+  /* z */ 546
 };
 
 /*
@@ -56,7 +56,7 @@
   /* m */ {  1,  0,  0,  0,  7,  0,  0,  0,  0,  0, 10,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 16 },
   /* n */ {  0,  1,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  5,  8, 10,  0,  0,  0,  0,  0, 17,  0,  0,  0,  0,  0 },
   /* o */ {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  2,  5,  0,  0,  0,  0,  0,  0,  9,  0, 11,  0,  0,  0 },
-  /* p */ {  1,  0,  3,  0,  4,  0,  0,  0,  0,  0,  0,  0,  0,  0,  7, 10,  0,  0, 17, 18, 27,  0, 28,  0, 29,  0 },
+  /* p */ {  1,  0,  3,  0,  4,  0,  0,  0,  0,  0,  0,  0,  0,  0,  7,  9,  0,  0, 16, 17, 26,  0, 27,  0, 28,  0 },
   /* q */ {  2,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0 },
   /* r */ {  0,  0,  0,  0,  0,  0,  0,  0, 12,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 14, 19,  0,  0,  0,  0 },
   /* s */ {  2,  6, 15,  0, 19, 23,  0, 25, 26,  0,  0, 29, 31, 35, 39, 41,  0, 49,  0, 50,  0, 62, 63,  0, 64,  0 },
@@ -69,4 +69,4 @@
   /* z */ {  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0 }
 };
 
-static const int command_count = 560;
+static const int command_count = 559;