Let AHC compute Content-length, make byteArrayBody take an Aexpression
Rename sspBody into sspTemplateBody, fileBody into elTemplateBody, make ssp directly expose Session
Make AkkaDefaults extend AskSupport
Make BaseActor an abstract class as it has non abstract methods
Reduce java conversions garbage
Minor clean up
Support basicAuth configuration at HttpProtocolConfig level, close #1022
Add built-in extractor for dumping Session on request failure, close #1023