Stable: Major updates and bug-fixes

Changes/bug-fixes:

• Add target info for NRF51822
  • Update target records with armcc compatible targets
• Add fix for issue #45 (ignore import errors message)
• Merged pull request #46 (greentea ignores import errors)
• Add --plain switch to disable colorful (colorama) logging
• Add mutext protection for log messages
• Add missing mock module dependency to setup.py (used in unit testing)
• Polishing of few license entries