Added a new function strContains, which can be used in template expressions.

strContains(str, subStr) - checks whether a string contains a
particular substring.
Changed the syntax for creating the Map literal.

Instead of square brackets ([...]) now used braces ({...}).
Added a new function isNonnull, which can be used in template expressions.
    
isNonnull(value) - returns true if the given value is both defined and
not the value null.
In the CALL command can now specify the name of the template from
another namespace.

Example: {call mynamespace.test.helloWorld /}