package/nodejs: bump version to 6.0.0

package/nodejs: bump version to 6.0.0

See https://nodejs.org/en/blog/release/v6.0.0/

The patches from 5.11.0 have been copied to 6.0.0 with the following
changes:

 - Removed 0001-Remove-dependency-on-Python-bz2-module.patch,
   0003-Fix-va_list-not-declared.patch and
   0004-Fix-support-for-uClibc-ng.patch as all 3 have been fixed upstream
 - Renamed 0002-gyp-force-link-command-to-use-CXX.patch to
   0001-gyp-force-link-command-to-use-CXX.patch

Signed-off-by: Martin Bark <martin@barkynet.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>