A factory for creating a EL context object that will be used to evaluate a target object of an EL expression.
Note this ELContextFactory is not used at parse time, only evaluation time. Therefore, factories should not be
concerned with setting up parse-time context attributes such as the variable mapper and function mapper that play no
part during expression evaluation.
Configures and returns an ELContext to be used in evaluating EL expressions on the given base target
object. In certain environments the target will be null and the base object of the expression is expected to be
resolved via the ELContext's ELResolver chain.
target - The base object for the expression evaluation
ELContext The configured ELContext instance for evaluating expressions.