patch 9.0.0700: there is no real need for a "big" build

Problem:    There is no real need for a "big" build.
Solution:   Move common features to "normal" build, less often used features
            to the "huge" build. (Martin Tournoij, closes #11283)
diff --git a/src/auto/configure b/src/auto/configure
index 9e2512d..bcb40a7 100755
--- a/src/auto/configure
+++ b/src/auto/configure
@@ -1523,7 +1523,7 @@
   --with-view-name=NAME   what to call the View executable
   --with-global-runtime=DIR    global runtime directory in 'runtimepath', comma-separated for multiple directories
   --with-modified-by=NAME       name of who modified a release version
-  --with-features=TYPE    tiny, normal, big or huge (default: huge)
+  --with-features=TYPE    tiny, normal or huge (default: huge)
   --with-compiledby=NAME  name to show in :version message
   --with-lua-prefix=PFX   Prefix where Lua is installed.
   --with-luajit           Link with LuaJIT instead of Lua.
@@ -5220,7 +5220,8 @@
 
 
 case "$features" in
-  small) features="tiny" ;;
+  small) features="tiny"   ;;
+  big)   features="normal" ;;
 esac
 
 dovimdiff=""
@@ -5231,9 +5232,6 @@
   normal)	$as_echo "#define FEAT_NORMAL 1" >>confdefs.h
  dovimdiff="installvimdiff";
 			dogvimdiff="installgvimdiff" ;;
-  big)		$as_echo "#define FEAT_BIG 1" >>confdefs.h
- dovimdiff="installvimdiff";
-			dogvimdiff="installgvimdiff" ;;
   huge)		$as_echo "#define FEAT_HUGE 1" >>confdefs.h
  dovimdiff="installvimdiff";
 			dogvimdiff="installgvimdiff" ;;
@@ -12883,7 +12881,7 @@
 
 
 if test "$enable_canberra" = "maybe"; then
-  if test "$features" = "big" -o "$features" = "huge"; then
+  if test "$features" = "huge"; then
     { $as_echo "$as_me:${as_lineno-$LINENO}: result: Defaulting to yes" >&5
 $as_echo "Defaulting to yes" >&6; }
     enable_canberra="yes"
@@ -12957,7 +12955,7 @@
 
 
 if test "$enable_libsodium" = "maybe"; then
-  if test "$features" = "big" -o "$features" = "huge"; then
+  if test "$features" = "huge"; then
     { $as_echo "$as_me:${as_lineno-$LINENO}: result: Defaulting to yes" >&5
 $as_echo "Defaulting to yes" >&6; }
     enable_libsodium="yes"