doc: add more go1.3.txt items, sort.

LGTM=r
R=r
CC=golang-codereviews
https://golang.org/cl/70120044

doc/go1.3.txt

+cmd/go, go/build: support .m files (CL 60590044)
+cmd/go: add -exec to 'go run' and 'go test' (CL 68580043)
 cmd/gofmt: remove -tabwidth and -tabs flags (CL 52170043)
+crypto/tls: ServerName or InsecureSkipVerify (CL 67010043)
+crypto/tls: add DialWithDialer (CL 68920045)
+crypto/tls: report TLS version in ConnectionState (CL 68250043)
+crypto/x509: support CSRs (CL 49830048)
 liblink: pull linker i/o into separate liblink C library (CL 35790044)
+misc/benchcmp: removed and replaced by go.tools/cmd/benchcmp (CL 47980043)
 misc/dist: renamed misc/makerelease (CL 39920043)
+net/http: add Server.ErrorLog; log and test TLS handshake errors (CL 70250044)
+net/http: add Server.SetKeepAlivesEnabled (CL 69670043)
+net/http: add Transport.TLSHandshakeTimeout; set it by default (CL 68150045)
+net/http: add optional Server.ConnState callback (CL 69260044)
+net/http: use TCP Keep-Alives on DefaultTransport's connections (CL 68330046)
+net/http: use TCP keep-alives for ListenAndServe and ListenAndServeTLS (CL 48300043)
+net: add Dialer.KeepAlive option (CL 68380043)
+os/exec: fix Command with relative paths (CL 59580044)
+runtime/debug: add SetPanicOnFault (CL 66590044)
 runtime: output how long goroutines are blocked (CL 50420043)
+sync: add Pool (CL 41860043, 46010043)
 syscall: add NewCallbackCDecl to use for windows callbacks (CL 36180044)
-testing: diagnose buggy tests that panic(nil) (CL 55780043)
 testing: add b.RunParallel function (CL 57270043)
-misc/benchcmp: removed and replaced by go.tools/cmd/benchcmp (CL 47980043)
-cmd/go, go/build: support .m files (CL 60590044)
+testing: diagnose buggy tests that panic(nil) (CL 55780043)
 unicode: upgrade from Unicode 6.2.0 to 6.3.0 (CL 65400044)
-runtime/debug: add SetPanicOnFault (CL 66590044)
-crypto/tls: ServerName or InsecureSkipVerify (CL 67010043)
-crypto/tls: report TLS version in ConnectionState (CL 68250043)
-crypto/x509: support CSRs (CL 49830048)
-cmd/go: add -exec to 'go run' and 'go test' (CL 68580043)