Console: New /configfamily, /exportfamily

 - Export SSL cert on creation
 - new /certs page to show local SSL certs

/configreseed: Add 'Reset URL list' button for revert to default hosts (ticket #1554, thanks dzirtt@gmail.com)

 - Enable new NewsManager to load/store feed items on disk by UUID
 - News items are stored forever, not lost when they are removed from feed
 - News read in once at startup, not at every summary bar refresh
 - Convert old initialNews.xml and news.xml to NewsEntry format
 - Limit display to 2 news items in summary bar, /home and /console
 - New /news page to show all news

WIP, not yet hooked in

char encoding

change immediately when config changes, force republish
Router: RI rebuild locking

Full version is used as the su3 version.
Uses same su3 certs as release updates. Users may add additional certs
to ~/.i2p/certificates/router/ as necessary.
Copy echelon's reseed key for use as a router signer.
Unsigned update remains a separate option for now.
Various update subsystem cleanups.

since we cannot reliably detect DS-lite (ticket #1458)
Hide transport status on /peers unless routerconsole.advanced

i2psnark: Remove extra mime types in i2psnark web.xml;
added to Jetty's default by now, or in our mime.properties file

easy since we have multipart in console now
Better status feedback from update manager to console

  - Move multipart form support from susimail to jetty-i2p.jar
    so console can use it
  - Add multipart form support to formhandler.jsi and FormHandler.java
Reseed:
  - Fix zip magic number
  - Finish manual reseed from local file
package.html files for jetty-i2p.jar

  - Add form to manually reseed from zip or su3 URL
    (result status not yet working)
  - Add form to manually reseed from local zip or su3 file
    (not yet working, needs multipart/form-date moved from susimail)
  - Add form to create reseed zip file to share
    (working)
  - Backend support and refactoring in reseed code

   Added:
     nativeJbigiVersion()
     nativeGMPMajorVersion()
     nativeGMPMinorVersion()
     nativeGMPPatchVersion()
     nativeModInverse()
     nativeModPowCT()
   Support negative vaules in conversion functions
   Support negative base value in modPow()
   Throw ArithmeticException for bad arguments rather than crashing
   Switch to GMP 6.0.0
   New build targets
NativeBigInteger changes:
   Test improvements
   Version reporting
Crypto changes:
   Use constant time modPow() for signing and decryption
   Use native modInverse()