[Fix #529] Add EnforcedStyle config param to SpaceAroundBlockBraces.

Can be space_inside_braces or no_space_inside_braces.
Changed NoSpaceBeforeBlockParameters to SpaceBeforeBlockParameters.
Merge pull request #535 from jonas054/space_inside_block_braces_configurable

[Fix #529] Add EnforcedStyle config param to SpaceAroundBlockBraces.