asm: make textflag.h available outside of cmd/ld (CL 128050043)
bufio: handling of empty tokens at EOF changed, may require scanner change (CL 145390043)
+compress/flate, compress/gzip, compress/zlib: Reset support (https://codereview.appspot.com/97140043)
crypto/tls: add support for ALPN (RFC 7301) (CL 108710046)
crypto/tls: support programmatic selection of server certificates (CL 107400043)
flag: it is now an error to set a flag multiple times (CL 156390043)