Betacoin: all other changes

Here there are all other betacoin changes.

This patch should be split in other patches:
- all coin name change only on other patch
- all core changes must be splitted in other patches
  and need full details about them, for example:
  - transaction comment
  - checkpoints reset
  - chainparams changes
  - addrman changes
  - block generation changes

Changes done since old master:

- toolbar1.png removed (joulecoin), I did a grep of it and seems unused
- betacoin.png removed, I did a grep of it and seems unused
- unuseful change of file mode removed
- src/leveldb/build_config.mk removed because included on gitignore
- removed changes to src/version.cpp, was unuseful and know git commit
  of build can be useful
- removed some trailing whitespace
- fixed some formatting errors
- src/chainparams.cpp: removed seed4,5,6.betacoin.org not existing and
  3 should be sufficient

Reapplied these patches solving conflicts with betacoin changes:
- fix possible infinite loop in intro.cpp thread
- Move internal miner to separate miner.cpp module
- Minor miner fixes
- Remove #define loop from util.h
- Make sure new wallet variables are initialized

Note of possible improvements:
- some trailing whitespace should be removed