move git shell function to brew.sh

git is also used in analytics.sh

Library/Homebrew/cmd/update.sh

@@ -7,10 +7,6 @@
 
 source "$HOMEBREW_LIBRARY/Homebrew/utils/lock.sh"
 
-git() {
-  "$HOMEBREW_LIBRARY/ENV/scm/git" "$@"
-}
-
 git_init_if_necessary() {
   if [[ -n "$HOMEBREW_OSX" ]]
   then

Library/brew.sh

@@ -28,6 +28,10 @@ brew() {
   "$HOMEBREW_BREW_FILE" "$@"
 }
 
+git() {
+  "$HOMEBREW_LIBRARY/ENV/scm/git" "$@"
+}
+
 # Force UTF-8 to avoid encoding issues for users with broken locale settings.
 if [[ "$(locale charmap 2> /dev/null)" != "UTF-8" ]]
 then