Add installation instructions for Arch Linux

Installation:-Arch-Linux.md

@@ -0,0 +1,35 @@
+Go to some nice empty directory.
+
+```
+$ git clone http://github.com/simon987/Much-Assembly-Required
+$ git clone http://github.com/simon987/Much-Assembly-Required-Frontend
+
+# Note: for maven, choose openjdk version 8.
+$ sudo pacman -S mysql php maven
+
+$ cd Much-Assembly-Required-Frontend
+
+# The password is empty, so just hit <Enter>
+$ mysql -u root -p
+mysql> create database mar;
+mysql> grant all privileges on mar.* to 'mar'@'localhost' identified by 'mar';
+mysql> flush privileges;
+mysql> use mar;
+mysql> \. database.sql
+mysql> exit
+
+$ php -S localhost:8000
+```
+
+Now open a new terminal.
+
+In /etc/php/php.ini (owned by use sudo), uncomment the lines `extension=mysqli` and `extension=pdo_mysql`. Then do:
+
+```
+cd ../Much-Assembly-Required
+mvn install
+cd target
+java -jar server-1.2a.jar
+```
+
+Then opening http://localhost:8000 in a browser should give you the home page of your local installation.