fix some differences between ruby-build (refs #8)

plugins/python-build/bin/python-build

@@ -96,6 +96,10 @@ install_git() {
   install_package_using "git" 2 $*
 }
 
+install_svn() {
+  install_package_using "svn" 2 $*
+}
+
 install_jar() {
   install_package_using "jar" 1 $*
 }
@@ -130,7 +134,7 @@ make_package() {
 }
 
 compute_md5() {
-  if type md5 >/dev/null; then
+  if type md5 &>/dev/null; then
     md5 -q
   elif type openssl &>/dev/null; then
     local output="$(openssl md5)"
@@ -341,8 +345,8 @@ build_package_standard() {
   fi
 
   { ./configure --prefix="$PREFIX_PATH" $CONFIGURE_OPTS
-    make $MAKE_OPTS
-    make install
+    "$MAKE" $MAKE_OPTS
+    "$MAKE" install
   } >&4 2>&1
 }
 
@@ -354,8 +358,7 @@ build_package_autoconf() {
 build_package_python() {
   local package_name="$1"
 
-  {
-    "$PYTHON_BIN" setup.py install
+  { "$PYTHON_BIN" setup.py install
   } >&4 2>&1
 }
 
@@ -539,7 +542,7 @@ usage() {
 
 list_definitions() {
   { for definition in "${PYTHON_BUILD_ROOT}/share/python-build/"*; do
-      test -f "${definition}" && echo "${definition##*/}"
+      echo "${definition##*/}"
     done
   } | sort
 }