Replaced wire_string_t::operator+ with concat function.
Made datum_t constructor take scoped_ptr_t<wire_string_t>.
Made wire_string_t deserialize use scoped_ptr_t.
Made wire_string_t::create functions return a scoped_ptr_t.
Made equality operators short-cut when sizes differ.
Joined the dark side, made concat take references to wire_string_t.
Fixed comments, removed superstitious throw decls.
Merge branch 'next' into sam_wire_string_sanity
Explained how deserialization functions work.
I meant deserialization.
Changing parent dir fsync from guarantee to warning (to work on VirtualBox shared folders)
Making the message more specific, adding errno to warning
Printing err string in addition to errno for portability
Explicitly including utils.hpp
Upgrade packages in the AMI

Review 1425 by @mglukhovsky
Merge branch 'next' of github.com:rethinkdb/rethinkdb into next
Printing err string in addition to errno for portability
Explicitly including utils.hpp
http/json: fix wrong return type of cJSON_type_to_string

We return c style strings instead of strings of C++ String class.

Signed-off-by: Liu Aleaxander <Aleaxander@gmail.com>
http/json: be more informative about the json schema mismatch error

Before this patch, we might get error meessage like:
    info: HTTP request throw a schema_mismatch_exc_t with what = Expected object instead got: 2

However, we can tell user more by:
    info: HTTP request throw a schema_mismatch_exc_t with what = Expected 'object' instead got 'number': 2

Signed-off-by: Liu Aleaxander <Aleaxander@gmail.com>