RFR [9] 8039362: Read content-types.properties as a resource

[Chris Hegarty]

Following JDK-8004963: "URLConnection, downgrade normative reference to 
${java.home}/lib/content-types.properties", this bug [1] moves 
content-types.properties out of the image lib directory and into 
resources.jar ( to be loaded as a resources file ). This approach is 
acceptable, since the file is not expected to be user editable.

Webrev:
   http://cr.openjdk.java.net/~chegar/8039362/00/webrev/

MimeTable.save(String) can be simply removed since it is never called, 
and editing the default table is not supported.

The motive for this bug is the modular JDK where we need the flexibility 
to put anything that is module-private into a module-private location. 
In this case it would appear that the above files are not a supported 
interface and so should move to a location that should be read as 
resources.

-Chris.

[1] https://bugs.openjdk.java.net/browse/JDK-8039362