Boost: Update 7

Boost: Update 7

Major fixes:
 - Due to incompatibility issues with other packages which depend upon boost
   libraries being built with system names (without name tags):
   - multi-thread support is now active by default.
   - boost libraries do not have name tags by default.

 - Added "Use tagged names." options
   - This option provides access to Single threaded option and Debug option.
   - The use of name tags is required to build the debug and single threaded
     versions.

Minor fixes (proposed by Thess):
 - "Compile Static Libraries" is active by default
 - "Use shared version of C and C++ runtimes for shared libraries" is now active
   by default
 - Several dependency notation fixes

Signed-off-by: Carlos M. Ferreira <carlosmf.pt@gmail.com>