minor: restore squashed README.md
CXX-53 Remove unused signal handler code
CXX-53 Remove StartupTests
CXX-53 Remove server specific debugging facilities
CXX-53 Remove server oriented shutdown and exit mechanisms
CXX-53 Remove stack trace and assertion counting mechanisms
CXX-53 Remove backtrace support
CXX-53 The MONGO_OPTIMIZED_BUILD macro has no effect in the driver codebase
CXX-153 Remove dependency on boost filesystem
CXX-86 The driver doesn't vendorize boost so the hack is no longer relevant
CXX-158 Add GridFS tests to increase coverage
CXX-158 improvements based on Andrew's comments
CXX-158 use L_tmpnam and touchup some comments