Bug 167450 [DataBinding] Get rid of bind support factory magic
I finally realized that we don't need that other magic factory. I'll move fillBindSpecDefaults() and the methods it calls (createConverter, createValidator etc) to a new class DefaultBindSpec. Clients who want default validators and converters created for them just create a DefaultBindSpec as opposed to a (rather empty) BindSpec. I will also move the early type checking into DefaultBindSpec to make it optional as well.
bundles/org.eclipse.core.databinding/src/org/eclipse/core/databinding/BindSpec.java
* @see DataBindingContext#POLICY_EXPLICIT
	 */
	public Integer getTargetUpdatePolicy() {
		return targetUpdatePolicy;
	}
	/**
	 * @return a validator for validation of partial target values 
	 */
	public IValidator getPartialTargetValidator() {
		return partialTargetValidator;
	}
	/**
	 * Returns the validator to be used, or <code>null</code> if a default
	 * validator should be used.
	 * 
	 * @return the validator, or <code>null</code>
	 */
	public IValidator getTargetValidator() {
		return targetValidator;
	}
	/**
	 * Returns the validate policy to be used for validating changes to the
	 * target
	 * 
	 * @return the update policy, or <code>null</code> if unspecified
	 * 
	 * @see DataBindingContext#POLICY_AUTOMATIC
	 * @see DataBindingContext#POLICY_EXPLICIT
	 */
	public Integer getValidatePolicy() {