autoconf: GIT_CONF_APPEND_LINE -> GIT_CONF_SUBST

The new name fits better with the macro signature, and underlines the
similarities with the autoconf-provided macro AC_SUBST (which will be
made even more pronounced in planned future commits).

Once again, no semantic change is intended, and indeed no change to the
generated configure script is expected.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

configure.ac

@@ -3,8 +3,8 @@
 
 ## Definitions of private macros.
 
-# GIT_CONF_APPEND_LINE(VAL, VAR)
-# ------------------------------
+# GIT_CONF_SUBST(VAL, VAR)
+# ------------------------
 # Append the line "VAR=VAL" to file ${config_append}
 AC_DEFUN([GIT_CONF_APPEND_LINE],
          [echo "$1=$2" >> "${config_append}"])
@@ -34,8 +34,8 @@ AC_DEFUN([GIT_CONF_APPEND_PATH],
 	if test -n "$2"; then
 		GIT_UC_PROGRAM[]_PATH=$withval
 		AC_MSG_NOTICE([Disabling use of ${PROGRAM}])
-		GIT_CONF_APPEND_LINE([NO_${PROGRAM}], [YesPlease])
-		GIT_CONF_APPEND_LINE([${PROGRAM}_PATH], [])
+		GIT_CONF_SUBST([NO_${PROGRAM}], [YesPlease])
+		GIT_CONF_SUBST([${PROGRAM}_PATH], [])
 	else
 		AC_MSG_ERROR([You cannot use git without $1])
 	fi
@@ -45,7 +45,7 @@ AC_DEFUN([GIT_CONF_APPEND_PATH],
 	else
 		GIT_UC_PROGRAM[]_PATH=$withval
 		AC_MSG_NOTICE([Setting GIT_UC_PROGRAM[]_PATH to $withval])
-		GIT_CONF_APPEND_LINE([${PROGRAM}_PATH], [$withval])
+		GIT_CONF_SUBST([${PROGRAM}_PATH], [$withval])
 	fi
     fi
     m4_popdef([GIT_UC_PROGRAM])])
@@ -67,7 +67,7 @@ AC_DEFUN([GIT_PARSE_WITH],
 	NO_[]GIT_UC_PACKAGE=
 	GIT_UC_PACKAGE[]DIR=$withval
 	AC_MSG_NOTICE([Setting GIT_UC_PACKAGE[]DIR to $withval])
-	GIT_CONF_APPEND_LINE([${PACKAGE}DIR], [$withval])
+	GIT_CONF_SUBST([${PACKAGE}DIR], [$withval])
     fi
     m4_popdef([GIT_UC_PACKAGE])])
 
@@ -87,7 +87,7 @@ AC_DEFUN([GIT_PARSE_WITH_SET_MAKE_VAR],
 		     [a value for $1 ($2).  Maybe you do...?])
   fi
   AC_MSG_NOTICE([Setting $2 to $withval])
-  GIT_CONF_APPEND_LINE([$2], [$withval])
+  GIT_CONF_SUBST([$2], [$withval])
  fi)])# GIT_PARSE_WITH_SET_MAKE_VAR
 
 #
@@ -150,7 +150,7 @@ AC_ARG_WITH([sane-tool-path],
   else
     AC_MSG_NOTICE([Setting SANE_TOOL_PATH to '$withval'])
   fi
-  GIT_CONF_APPEND_LINE([SANE_TOOL_PATH], [$withval])],
+  GIT_CONF_SUBST([SANE_TOOL_PATH], [$withval])],
   [# If the "--with-sane-tool-path" option was not given, don't touch
    # SANE_TOOL_PATH here, but let defaults in Makefile take care of it.
    # This should minimize spurious differences in the behaviour of the
@@ -169,7 +169,7 @@ AC_ARG_WITH([lib],
   else
 	lib=$withval
 	AC_MSG_NOTICE([Setting lib to '$lib'])
-	GIT_CONF_APPEND_LINE([lib], [$withval])
+	GIT_CONF_SUBST([lib], [$withval])
   fi])
 
 if test -z "$lib"; then
@@ -205,7 +205,7 @@ AC_ARG_ENABLE([jsmin],
 [
   JSMIN=$enableval;
   AC_MSG_NOTICE([Setting JSMIN to '$JSMIN' to enable JavaScript minifying])
-  GIT_CONF_APPEND_LINE([JSMIN], [$enableval]);
+  GIT_CONF_SUBST([JSMIN], [$enableval]);
 ])
 
 # Define option to enable CSS minification
@@ -215,7 +215,7 @@ AC_ARG_ENABLE([cssmin],
 [
   CSSMIN=$enableval;
   AC_MSG_NOTICE([Setting CSSMIN to '$CSSMIN' to enable CSS minifying])
-  GIT_CONF_APPEND_LINE([CSSMIN], [$enableval]);
+  GIT_CONF_SUBST([CSSMIN], [$enableval]);
 ])
 
 ## Site configuration (override autodetection)
@@ -256,7 +256,7 @@ AS_HELP_STRING([],           [ARG can be also prefix for libpcre library and hea
 	USE_LIBPCRE=YesPlease
 	LIBPCREDIR=$withval
 	AC_MSG_NOTICE([Setting LIBPCREDIR to $withval])
-	GIT_CONF_APPEND_LINE([LIBPCREDIR], [$withval])
+	GIT_CONF_SUBST([LIBPCREDIR], [$withval])
     fi)
 #
 # Define NO_CURL if you do not have curl installed.  git-http-pull and