code: public CloudhopperBuilder password(String... password) {
  		for (String p : password) {
  			if (p != null) {
  				passwords.add(p);
  			}
  		}
  		return this;
  	}
docs: The password parameter is used by the SMSC to authenticate the identity
  of the binding ESME. The Service Provider may require ESME’s to provide a
  password when binding to the SMSC. This password is normally issued by
  the SMSC system administrator. The password parameter may also be used by
  the ESME to authenticate the identity of the binding SMSC (e.g. in the
  case of the outbind operation).
  
  The ESME may set the password to NULL to gain insecure access (if allowed
  by SMSC administration).
  
  You can specify a direct value. For example:
  
  <pre>
  .password("foo");
  </pre>
  
  <p>
  You can also specify one or several property keys. For example:
  
  <pre>
  .password("${custom.property.high-priority}", "${custom.property.low-priority}");
  </pre>
  
  The properties are not immediately evaluated. The evaluation will be done
  when the {@link #build()} method is called.
  
  If you provide several property keys, evaluation will be done on the
  first key and if the property exists (see {@link EnvironmentBuilder}),
  its value is used. If the first property doesn't exist in properties,
  then it tries with the second one and so on.
  
  @param password
  one value, or one or several property keys
  @return this instance for fluent chaining