- Fix "don't try to load native plugins"
  * This currently works because we don't ship with native viewers
  * Otherwise, the plugin OS,ARCH characterisation through ELF headers only
    works for Linux / FreeBSD where they have dedicated tags
  => This was only useful for Linux/i386 platforms anyway ATM
- Clean-ups
  * Re-indent -gnu -br -brs
  * Better split for RPC / NAPI level routines
  * Empty communication stream on RPC error so that next request can work
- Write the testsuite
  * RPC tests, basic types
  * RPC tests, NPAPI types (including NPVariant)
  * NPAPI plugins (compliance checks, error recovery, async requests)
- XPCOM support
  * Parse XPT files?
  * Mix native / marshaled components?
- Windows plugins support
  * Import minimal GLib functions (hashes, etc.)
  * Split toolkit specific code (npviewer-{x11,gtk,win}.c)
  * Use winelib + override win32 socket to support AF_UNIX (Linux "native")
