Improved "gopherjs build" command.
Improved "gopherjs build" command.

rasata/gopherjs,govlas/gopherjs,albrow/gopherjs,roth1002/gopherjs,ebroder/gopherjs,bpowers/gopherjs,gopherjs/gopherjs,jargv/gopherjs,nmfzone/gopherjs,Yanjing123/gopherjs,albrow/gopherjs,albrow/gopherjs,rasata/gopherjs,gopherjs/gopherjs,govlas/gopherjs,Archs/gopherjs,roth1002/gopherjs,jargv/gopherjs,nmfzone/gopherjs,Yanjing123/gopherjs,nmfzone/gopherjs,roth1002/gopherjs,ebroder/gopherjs,rasata/gopherjs,jeremyschlatter/gopherjs,jeremyschlatter/gopherjs,flimzy/gopherjs,gopherjs/gopherjs,gopherjs/gopherjs,jeremyschlatter/gopherjs,Yanjing123/gopherjs,govlas/gopherjs,Archs/gopherjs,flimzy/gopherjs,ebroder/gopherjs,bpowers/gopherjs,jargv/gopherjs,gopherjs/gopherjs,bpowers/gopherjs,flimzy/gopherjs,Archs/gopherjs