Add build output folder (target) to .gitignore
Reworked configuration with an eye towards issue #117. Missing jar files and other problems that prevent a class from being instantiated will now cause p:step-available to return false. There's also a static isAvailable() method that steps can use for finer control.
Merge pull request #123 from sharwell/gitignore-target

Add build output folder (target) to .gitignore
Added commnt and newline
Resolve issue #125 by updating pom.xml by hand (marking Saxon optional)
Use generics properly
Call static method directly
Updated compilerArgs; always build with -Xlint -Xlint:-serial