Update PHP Version to 5.4.37 in Ubuntu 12.04

PHP 5.4.37 is not available in Ubuntu 12.04 repositories. You may update your PHP version from some other repositories (PPA).

I am going to use ondrej's oldstable PPA for updating PHP. You will have to run the following commands to complete the process:

1. sudo apt-get install python-software-properties

2. sudo add-apt-repository ppa:ondrej/php5-oldstable

3. sudo apt-get update

4. sudo apt-get install php5

The latest version of PHP will be installed.