Added documentation for how to setup sinopia on a linux server

SERVER.md

@@ -0,0 +1,51 @@
+This is mostly basic linux server configuration stuff but I felt it important to document and share the steps I took to get sinopia running permanently on my server. You will need root (or sudo) permissions for the following.
+
+## Running as a separate user
+First create the sinopia user:
+```bash
+$ sudo adduser --disabled-login --gecos 'Sinopia NPM mirror' sinopia
+```
+
+You create a shell as the sinopia user using the following command:
+```bash
+$ sudo su sinopia
+$ cd ~
+```
+
+The 'cd ~' command send you to the home directory of the sinopia user. Make sure you run sinopia at least once to generate the config file. Edit it according to your needs.
+
+## Keeping sinopia running forever
+We can use the node package called 'forever' to keep sinopia running all the time.
+https://github.com/nodejitsu/forever
+
+First install forever globally:
+```bash
+$ sudo npm install -g forever
+```
+
+Make sure you've started sinopia at least once to generate the config file and write down the created admin user. You can then use the following command to start sinopia:
+```bash
+$ forever start `which sinopia`
+```
+
+You can check the documentation for more information on how to use forever.
+
+## Surviving server restarts
+We can use crontab and forever together to restart sinopia after a server reboot.
+When you're logged in as the sinopia user do the following:
+
+```bash
+$ crontab -e
+```
+
+This might ask you to choose an editor. Pick your favorite and proceed.
+Add the following entry to the file:
+```
+@reboot /usr/bin/forever start /usr/lib/node_modules/sinopia/bin/sinopia
+```
+
+The locations may vary depending on your server setup. If you want to know where your files are you can use the 'which' command:
+```bash
+$ which forever
+$ which sinopia
+```