Added properties files for versioning.
Inserted x-ctct-request-source header in every request made to constant contact API.
Update pom.xml.
Merge branch 'master' of https://github.com/constantcontact/java-sdk
Added new line in properties file.
Read SDK version from resource properties file.
Updated final jar name to include current version.
Updated version in pom to "v2".
Removed comment from pom.xml
Removed unnecessary properties file.
Removed unnecessary plugins from maven.
Updated version to 2.1.5.
Revert "Removed unnecessary plugins from maven."

This reverts commit 43effce2a7f93bdff7e8d96a947b041218a8b0e4.
Removed unnecessary plugins from maven.
Updated version to 2.1.5.
Changed the method for reading package version.
Merge pull request #38 from halusstefan/master

Added versioning track header implementation