Fix simple language code samples

n this page:
http://fusesource.com/docs/esb/4.0/fmr_nmr/FMRS.LEP.html
For example, the predicate, simple("header.timeOfDay = '14:30'"), tests whether the timeOfDay header in the incoming message is equal to 14:30.
The simple language does not support any operators, so you can not do as above.

It can only be used for testing the existence of a property/header/body/system property etc.
And to concat strings using the ${ } placeholders - such a "The time is ${header.timeOfDay}"