Changes for certificate signing stuff in Akami.
Merge branch 'master', remote-tracking branch 'origin' into certificate_signing
changed the config to an actual class
removed the Object#blank? extension
updated the changelog
added Savon.client shortcut
re-added integration specs
ensure to release using ruby 1.8
fix for ruby 1.8
add lib to yardopts
Allow the user to set the header as a string
refactored header_for_xml
updated the changelog [ci skip]
config: refactored to set defaults on initialize
config: simplified and extracted logging
config: replace NullLogger with $stdout default
updated development dependencies
config: pass it through - fixes #84
add an option to pretty print xml for the log

closes #280 and #256
updated the changelog [ci skip]