Termux is effectively a single-user system so chown:ing
does not make much sense.

Without this patch npm fails with EPERM on chown
for cache.json when first building the local index.
diff -u -r ../node-v4.4.3/deps/npm/lib/cache/update-index.js ./deps/npm/lib/cache/update-index.js > npm-avoid-chown.patch
--- ../node-v4.4.3/deps/npm/lib/cache/update-index.js	2016-04-12 19:42:04.000000000 +0000
+++ ./deps/npm/lib/cache/update-index.js	2016-04-19 09:29:54.634171804 +0000
@@ -4,7 +4,7 @@
 var assert = require('assert')
 var path = require('path')
 var mkdir = require('mkdirp')
-var chownr = require('chownr')
+var chownr = function(path, uid, gid, cb) { cb(null); }
 var npm = require('../npm.js')
 var log = require('npmlog')
 var cacheFile = require('npm-cache-filename')