Set the boost path to a directory that has its own version number. This has the advan...

Set the boost path to a directory that has its own version number. This has the advantage that we can now atomically add a new version of boost and delete the previous one, rather than doing the three-step we previously had (add new, delete old, move over new; or delete old and add new) that typically also confuses svn and leads to directories that are a mess.

git-svn-id: https://svn.dealii.org/trunk@23705 0785d39b-7218-0410-832d-ea1e28bc413d