Betacoin: some coin name change only

This patch should be splited in other patches:
- changes of coin name on qt strings insert also on locales
- changes of coin name on text strings
- changes of coin name on core

Note of possible improvements:
- remove coin name changes only from comments
  on core code
- remove changes of coin name on qt strings translated
  by locales for change them only 1 time instead 3,
  require remove of them also on source fields of locales
Betacoin: build changes

Changes from old master:
- changed coin name on share/setup.nsi to not
  conflict with bitcoin installation
Betacoin: mainly core changes

This patch should be splitted in other patches:
and with full details about them, for example:
  - add of comment field to transactions
  - checkpoints reset
  - chainparams changes
  - block generation changes

Changes done since old master:
- 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
- splitted coin name changes only and some minor core changes to
  another patches

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
- Bugfix: Store last/next wallet resend times unique per CWallet object

Note of possible improvements:
- some formatting errors should be fixed
- improve src/chainparams.cpp
Betacoin: addrman changes

Description and justification of these changes must be added.
Betacoin: added betacoin developers to copyrigth lines

Changes from old master:
- added on unique copyrigth line instead additional
Betacoin: version

Set correct version and flag as release even if is not stable version

Changes from old master:
- increased build version from 4 to 5
- changed CLIENT_VERSION_IS_RELEASE to false until the improvements
  will are finished and will be well tested