* Config files: Add some encoding help

* DataHelper, Router:
      - Save config files in UTF-8 rather than the default encoding,
        since we read them in UTF-8
    * jetty.xml: Change encoding to UTF-8
    * logs.jsp: Add system encoding
    * NTCP: Clean up clock skew shitlist message
    * Shitlist: Clean up expire message
    * WorkingDir: Ensure modified files are processed with UTF-8 encoding

apps/i2psnark/i2psnark.config

@@ -1,3 +1,4 @@
+# NOTE: This I2P config file must use UTF-8 encoding
 #
 # If you have a 'split' directory installation, with configuration
 # files in ~/.i2p (Linux) or %APPDATA%\I2P (Windows), be sure to