Translations update: pull from Transifex

- added languages in bitcoin.qrc: bs, ca, cy, eo, gu_IN, hi_IN, ja, la,
  lv_LV and th_TH (some translations files were already in src/qt/locale
  but not added in the .qrc file
Merge pull request #2482 from Diapolo/TX-pull

Translations update: pull from Transifex
Make sure we always have a node to do IBD from

This introduces the concept of the 'sync node', which is the one we
asked for missing blocks. In case the sync node goes away, a new one
will be selected.

For now, the heuristic is very simple, but it can easily be extended
later to add better policies.
Add bytessent, bytesrecv and syncnode to getpeerinfo