Missing parentheses in doc

[eximius313]

Here: https://deadbolt-java.readme.io/docs/template-constraints
you have:

Scala
@subjectPresentOr {
  this is protected
} {
  this will be shown if the constraint blocks the other content
}

and should be:

Scala
@subjectPresentOr() {
  this is protected
} {
  this will be shown if the constraint blocks the other content
}

I'd also add example of MyDeadboltHandler which can extend AbstractDeadboltHandler for clarity (because I needed to look for example implementation in the source code)

[schaloner]

Docs updated, thanks for the report.