ubuntu npm install not installing dependencies or dev dependencies - node.js

Question

I have cloned a project's repo (that was made on a mac) down to my ubuntu machine and I hit a lot of problems getting node to work. I feel like I'm at the final hurdle.
I can't get npm install to install dependencies according to the package.json file.
Note in the following, I have used <repo description>, <repo name> and <app name>, where appropriate, for privacy.
package.json (git repo name removed for privacy):
{
"name": "<repo name>",
"version": "1.0.0",
"engines": {
"npm": "2.1.x"
},
"description": "<repo description>",
"main": "index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"postinstall": "bower install",
"start": "node server.js"
},
"repository": {
"type": "git",
"url": "git+https://github.com/<repo name>"
},
"author": "",
"license": "ISC",
"bugs": {
"url": "https://github.com/<repo name>/issues"
},
"homepage": "https://github.com/<repo name>#readme",
"devDependencies": {
"grunt": "^0.4.5",
"grunt-contrib-sass": "^0.9.2",
"grunt-contrib-watch": "^0.6.1",
"jasmine-core": "^2.3.4",
"karma": "^0.13.9",
"karma-chrome-launcher": "^0.2.0",
"karma-jasmine": "^0.3.6",
"karma-phantomjs-launcher": "^0.2.1",
"phantomjs": "^1.9.18",
"protractor": "^2.2.0"
},
"dependencies": {
"bower": "^1.5.2",
"ejs": "^2.3.4",
"express": "^4.13.3",
"http-server": "^0.8.0"
},
"directories": {
"test": "test"
}
}
When running npm install, I get:
npm WARN package.json <app name>#1.0.0 No README data
> <app name>#1.0.0 postinstall /home/andrew/projects/<app name>
> bower install
andrew:<app name>$
When running sudo npm install, I get:
npm WARN package.json <app name>#1.0.0 No README data
npm WARN cannot run in wd <app name>#1.0.0 bower install (wd=/home/andrew/projects/<app name>)
node -v returns v0.12.7, nodejs -v returns v0.10.25, npm -v returns 2.12.1, bower -v returns 1.5.2, but grunt -v returns:
No command 'grunt' found, did you mean:
Command 'grun' from package 'grun' (universe)
grunt: command not found
(just proof that grunt has not been installed as it should).