Apple recently updated the docs on dispatch_once to point out
that the storage for the dispatch_once_t must be static or global,
but not something that was ever used before as the implementation
doesn't use a memory barrier.  So we drop the use and create the
semaphore when needed and use an atomic swap deal with any
threading races.

Add support for Xcode 8.3 to the build helper.

Add some new ignores for things generated in conformance.

* Issue #2211: Addressing GCC warning on enumeral/non-enumeral in conditional expression.

* Updated per 80 character wrap.

Added a workaround to allow building for NaCl

arm-nacl-clang seems to produce a mysterious compiler error when it
encounters __builtin_clzll, so when we are building for NaCl, let's
avoid that in favor of the portable implementation of
Log2FloorNonZero64.

Raise the recursion limit to 100 to match other languages.

Changed go_package for plugin.proto.

Conformance tests for JavaScript (Node.js). 15 tests are failing.

Add FormatEnumsAsIntegers support for Json Format. Scale JsonFormatter.Settings for multi options.

Compile the Java proto runtime with Java 6

in order to avoid errors related to generics when 
building user code in newer versions of Java.

migrate delimited messages functions to util package

Remove duplicated copyright statement

fix attributes warning

Ruby: only link against specific version of memcpy if we're using glibc

Add preserve_proto_field_names option to JsonPrintOptions

We have some special code in wrap_memcpy.c to ensure that we use the
2.2.5 version of memcpy, for compatibility with older versions of glibc.
However, we need to make sure we only attempt to do this when we are
actually building with glibc, so that the code can also build
successfully against other libc implementations such as musl.

DefaultValueObjectWriter should populate oneof message field

This option will be prepended to generated classes of all messages in
the containing file.

Fix freebsd build.

Add a notice for nano.

We no longer supports nano and recommend protobuf lite over nano for
Android users.

Changed scope of Java deps to "test".

Ruby: fixed Message#to_h for map fields.

JS: ensure that extension values are serialized even if they're falsy