[RFC] vim-patch:7.4.483, vim-patch:7.4.485, vim-patch:7.4.488

Makefile/`.proto` changes omitted in the diffs posted here for brevity.

7.4.483 introduces some changes, 7.4.485 removes these and replaces them with an alternative, 7.4.488 modifies a test introduced in the first patch.

### 7.4.483

```
Problem:    A 0x80 byte is not handled correctly in abbreviations.
Solution:   Unescape special characters. Add a test. (Christian Brabandt)

https://code.google.com/p/vim/source/detail?r=v7-4-483
```

Original patch:
```diff
diff --git a/src/nvim/getchar.c b/src/nvim/getchar.c
--- a/src/nvim/getchar.c
+++ b/src/nvim/getchar.c
@@ -4443,6 +4443,7 @@ check_abbr(c, ptr, col, mincol)
 #endif
     int		is_id = TRUE;
     int		vim_abbr;
+    int		qlen;		/* length of q, CSI/K_SPECIAL unescaped */
 
     if (typebuf.tb_no_abbr_cnt)	/* abbrev. are not recursive */
 	return FALSE;
@@ -4520,6 +4521,19 @@ check_abbr(c, ptr, col, mincol)
 #else
 	mp = first_abbr;
 #endif
+	qlen = mp->m_keylen;
+	if (vim_strbyte(mp->m_keys, K_SPECIAL) != NULL)
+	{
+	    char_u	*q = vim_strsave(mp->m_keys);
+
+	    /* might have CSI escaped mp->m_keys */
+	    if (q != NULL)
+	    {
+		vim_unescape_csi(q);
+		qlen = STRLEN(q);
+		vim_free(q);
+	    }
+	}
 	for ( ; mp;
 #ifdef FEAT_LOCALMAP
 		mp->m_next == NULL ? (mp = mp2, mp2 = NULL) :
@@ -4528,7 +4542,7 @@ check_abbr(c, ptr, col, mincol)
 	{
 	    /* find entries with right mode and keys */
 	    if (       (mp->m_mode & State)
-		    && mp->m_keylen == len
+		    && qlen == len
 		    && !STRNCMP(mp->m_keys, ptr, (size_t)len))
 		break;
 	}
diff --git a/src/nvim/testdir/test_mapping.in b/src/nvim/testdir/test_mapping.in
new file mode 100644
--- /dev/null
+++ b/src/nvim/testdir/test_mapping.in
@@ -0,0 +1,15 @@
+Test for mappings and abbreviations
+
+STARTTEST
+:so small.vim
+:so mbyte.vim
+: " abbreviations with р (0x80) should work
+:inoreab чкпр   vim
+GAчкпр 
+
+:/^test/,$w! test.out
+:qa!
+ENDTEST
+
+test starts here:
+
diff --git a/src/nvim/testdir/test_mapping.ok b/src/nvim/testdir/test_mapping.ok
new file mode 100644
--- /dev/null
+++ b/src/nvim/testdir/test_mapping.ok
@@ -0,0 +1,2 @@
+test starts here:
+vim
diff --git a/src/nvim/version.c b/src/nvim/version.c
--- a/src/nvim/version.c
+++ b/src/nvim/version.c
@@ -742,6 +742,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    483,
+/**/
     482,
 /**/
     481,
```