First SSH Plugin Test
Merge branch 'master' of https://github.com/uhafner/acceptance-test-harness into docker-scp-plugin
Added second ssh plugin test and added FIXMEs for BUGs moved ssh keys again because of convention used by kawaguchi
Implemented SHA hashing for detecting dockerfile changes
code clean up
Merge branch 'master' of https://github.com/uhafner/acceptance-test-harness into docker-build
Immediate fixes still WIP
added @author
Merge branch 'master' of https://github.com/uhafner/acceptance-test-harness into docker-build
Fixed war file dockerfile bug
Merge branch 'master' of https://github.com/uhafner/acceptance-test-harness into docker-build
rewrote tests with helper functions and one additional test
further refactoring
further testing
added another test with allow exec
Ported svnTests to latest svn plugin version.

Marked classes and methodes only used by the deprecated test class also as deprecated.

Tidied up docker container and its dependencies.

Changed svn docker user to "svnUser" to prevent possible name overlaps.

 Fixed some typos, messages and jdoc
merge and remove comments
removed debugging sysout
Tweaked test cases to prevent errors caused by to fast test execution
Permit test harness to use http proxy settings

This pull request permits the test harness to use
http proxy settings from both maven settings
and command line arguments.

Artifact Resolution was refactored to be contained
in a single helper class ArtifactResolverUtil.java

[FIXED JENKINS-23113]