Add script to compile all the code.

Change-Id: Ibb5b9b9c8295cb68666ef277f33603ab0ca7856d

all.bash

diff --git a/all.bash b/all.bash
new file mode 100644
index 0000000..76f17aa
--- /dev/null
+++ b/all.bash
@@ -0,0 +1,18 @@
+#!/bin/bash
+
+for sub in manifest \
+gitiles \
+cache \
+fs \
+cmd/gitfs-expand-manifest \
+cmd/gitfs-multifs \
+cmd/gitfs-manifestfs \
+cmd/gitfs-populate \
+cmd/gitfs-gitilesfs \
+cmd/gitfs-deref-manifest \
+  ; do
+  p=github.com/google/gitfs/${sub}
+  go clean $p
+  go test $p
+  go install $p
+done