De-duplicate code that base64 encodes strings in SecurityHelpers.
Remove various unneeded parens in SecurityHelpers.
Add myself to the contributors file.
Fixed comment for devMode

* Standardized productionMode comment with others
DoubleField can be set from JInt
IntField/LongField can be set from JDouble
Updated contributors.md
Cleaned up Double/Int/LongField imports
Adding ajaxEditableSelect to SHtml. Allows users to dynamically add new selections into an ajaxSelect.
* Updated sbt to 0.12.1
* Fixed a compiler error due to wring rebase
Added clearAttrs method to S
Fix the field() method in LiftScreen that uses an underlying field so it incorporates passes in validations as well as the validations on the underlying field.
Rename ComputeTransformRules->CanBind, #{computeTransform->apply}
Deprecate S.getHeader in favor of S.getResponseHeader.

Also deprecate S.getHeaders in favor of S.getResponseHeaders, as well as
adding an S.setResponseHeader (though S.setHeader is not deprecated as
it is clear that it refers to the response).
fixed compiler error due to missing closing }
Fixed some bugs in the Html5 writing routines
Update internal deprecated uses of getHeaders to getResponseHeaders.
Fix order of deprecation arguments in S.getHeader and S.getHeaders.
Updated to Lift 2.5-RC1

Also updated jetty dependency, logback, sbt and web plugin