misc/dist: rename to makerelease

The ambiguity has gone on too long.

R=golang-dev, minux.ma, r, dsymonds
CC=golang-dev
https://golang.org/cl/39920043

misc/makerelease/darwin/scripts/postinstall

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+GOROOT=/usr/local/go
+
+echo "Fixing permissions"
+cd $GOROOT
+find . -exec chmod ugo+r \{\} \;
+find bin -exec chmod ugo+rx \{\} \;
+find . -type d -exec chmod ugo+rx \{\} \;
+chmod o-w .

misc/makerelease/darwin/scripts/preinstall

@@ -0,0 +1,8 @@
+#!/bin/bash
+
+GOROOT=/usr/local/go
+
+echo "Removing previous installation"
+if [ -d $GOROOT ]; then
+	rm -r $GOROOT
+fi