Wake a sleeping plugin

Update pom.xml
Add README.md
Change Hudson to Jenkins
[JENKINS-15890] Avoid ExecutionPolicy errors

ByPass PowerShell ExecutionPolicy
[FIXED JENKINS-15890] support of exit code

PowerShell Plugin now support exit code to fail the build
Merge pull request #1 from damienfinck/master

[FIXED JENKINS-15890] PowerShell improvements