Issue #19613 Upgrade node to 0.8.20 and upgrade packages and use .x to g...

...et future patch releases.

I did not upgrade backbone because I ran into this error from a change in the newer version:
https://github.com/documentcloud/backbone/issues/2094

Backbone-relational was bumped to the 0.6.x patch release from 0.6.0. Moving to 0.7.0 requires the latest backbone release.

You will need to do the following to your existing repo:
# Rebuild node on 0.8.20:
> cd ~/node
> git checkout v0.8.20
> ./configure --prefix=/usr/local --openssl-libpath=/usr/local/lib
> make
> sudo make install
> #(enter your password)

# Reinstall npm packages:
> cd ~/xtuple/node-datasource
> sudo rm -r node_modules
> npm install

> cd ~/xtuple/node-datasource/xt
> sudo rm -r node_modules
> npm install

> cd ~/xtuple/lib/backbone-x
> sudo rm -r node_modules
> npm install