Remove unused variable handshake_complete
fixing js worker processes on older versions of v8
Merge branch 'v1.7.x' of github.com:rethinkdb/rethinkdb into v1.7.x
Had the makefile specify _FILE_OFFSET_BITS=64 and put a compile-time assertion into disk.cc for sizeof(off_t).
Removed size_t offset usages.
Fixed signed comparison errors in unit tests.
Made file_size be int64_t in verify_aligned_file_access.
Merge branch 'v1.7.x' into next

Conflicts:
	src/arch/io/disk.cc
	src/arch/io/disk.hpp
	src/unittest/mock_file.cc
	src/unittest/mock_file.hpp