Fix for APIKit flows

Fix for #14

Support for APM agent v1.6.0

• Support for v1.6.0 of Java APM agent
• Support for Mule timestamps instead of APM client own timestamps.
• More explicit property initialisation fixing propety files not being picked up.

Capture flowVars at steps

Added config option to capture flowVars as Span tags "FlowVar:xxx=yyy"

Updated to use attach API

Update to use Java APM client attach API

Support for domain based config

• It allows configuration of domain projects by adding configuration to domain config xml, instead of every individual file.
• The agent was updated to use Java APM agent version 1.4.0

Support for Elastic Java APM agent v1.3.0

v1.3.0-beta

added Java dashboard