Extracted a not-so-happy case from HappyPathHandshakeActorTest

This (I thought) will avoid a heisenbug reproduced when jenkins is 
under heavy load.
Merge pull request #90 from sortega/bugfix/69-heisenbug

Extracted a not-so-happy case from HappyPathHandshakeActorTest
Implemented Okpay client using ScalaXB.
Merge pull request #91 from gotoalberto/scalaxb

Implemented Okpay client using ScalaXB.