Similar to the functionality of loading System Properties, there is now an option to load Environment Variables. Closes #31

• Enable Environment Variables via runtime property bordertech.config.parameters.useEnvProperties=true
• Option to limit variables merged via property bordertech.config.parameters.useEnvPrefixes. Defaults to allow all.
• Ability to override the default config file name via a system or environment property BT_CONFIG_FILE=my-config.properties
• To be consistent with Environment and System property behaviour, the runtime property bordertech.config.parameters.useSystemOverWriteOnly now defaults to false which allows all system properties to be merged when system properties enabled. Use the optional runtime property bordertech.config.parameters.useSystemPrefixes to limit the properties merged.
• Option to append extra resources to the defined resources via config property bordertech.config.resources.append

Other changes:

• Latest qa-parent
• Fix travis sonar token