Adjust repo path dependencies.

Update .gitignore and configure.ac to deal with the recent directory
restructuring.
diff --git a/configure.ac b/configure.ac
index 412d3d1..e317d0a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -688,7 +688,7 @@
 dnl 
 
 dnl Set VERSION if source directory has an embedded git repository.
-if test -d "${srcroot}../.git" ; then
+if test -d "${srcroot}.git" ; then
   git describe --long --abbrev=40 > ${srcroot}VERSION
 fi
 jemalloc_version=`cat ${srcroot}VERSION`