Some enhancements re config data on command line.

 1. Display of --config-show now in column format, rather than just using print_r:

    $ phpcs --config-show
    jsl_path:    /home/kguest/bin/jsl
    testVersion: 5.3
    $

 2. Exceptions when writing to non-writable CodeSniffer.conf caught:

    $ phpcs --config-set testVersion 5.5
    Config file /usr/share/php/data/PHP_CodeSniffer/CodeSniffer.conf is not writable
    $
    $ phpcs --config-delete jsl_path
    Config file /usr/share/php/data/PHP_CodeSniffer/CodeSniffer.conf is not writable
    $
Merge branch 'master' of https://github.com/kenguest/PHP_CodeSniffer
Coding standards + changelog
Setting and removing config values now prints a message to confirm the action and show old values
Added readme, contrib and licence files to PEAR distribution (request #273)
Merge branch 'master' into phpcs-fixer

Conflicts:
	CodeSniffer.php
	CodeSniffer/CLI.php
	package.xml