PropertyConstantCreator and ApplicationPropertyConstantCreator incorrect UTF-8 encoding

There are actually several issues for the ApplicationPropertyConstantCreator:

the class comment does not resolve the artifactId and version

/** Property constants for ${project.artifactId} ${project.version} */
public class PropertyConstants {

UTF-8 characters might be encoded incorrectly (i had different results with different build tools on windows)

properties with a "." generate invalid java code:

<property id="complex.property" description="Gehälter in €">1000</property>

results in:

/** Geh�lter in � */
public static final String PROP_COMPLEX_._PROPERTY = "complex.property";

PropertyConstantCreator may encode UTF-8 characters incorrectly as well

person.salary=Gehälter in €!

/** Gehälter in �?�! */
public static final String PERSON_SALARY = "person.salary";

Possible solution for the second set of issues:

• Enforce UTF-8 writer (or add a property to configure the encoding)
• Field name should replace "." with "_"