These are BOSCO tarballs for several platforms.
They are the stripped tarballs from the 8.5.6 release.
They were built in the NMI lab from the head of 
V8_5_6-branch (f47dfa24bd19162).
The NMI run id was 376655
boscoinstaller is a copy of bosco_findplatform in the source tree.
bosco_quickstart is copied out of the source tree.