在Ubuntu上安装ruby-china

1.安装libpng

sudo apt-get install libpng-dev

2.安装imagemagick

sudo apt-get install imagemagick

3.安装MongoDB

参考文档：https://www.digitalocean.com/community/articles/how-to-install-mongodb-on-ubuntu-12-04

4.安装Redis

参考了discourse文档中关于安装redis的说明

sudo su -
mkdir /tmp/redis_install
cd /tmp/redis_install
wget http://redis.googlecode.com/files/redis-2.6.7.tar.gz
tar xvf redis-2.6.7.tar.gz
cd redis-2.6.7
make
make install
cd utils
./install_server.sh
# Press enter to accept all the defaults
/etc/init.d/redis_6379 start

5.安装memcached

sudo apt-get install memcached

6.安装ruby-china

git clone git://github.com/ruby-china/ruby-china.git
cd ruby-china
ruby setup.rb
# ensure that memcached has started up
rails s