[ruby-cvs:72598] k0kubun:r65498 (trunk): README.md: add wercker status badge [ci skip]

[k0kubun at ruby-lang.org]

k0kubun	2018-11-02 21:21:59 +0900 (Fri, 02 Nov 2018)

  New Revision: 65498

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=65498

  Log:
    README.md: add wercker status badge [ci skip]
    
    and show trunk branch's build status for travis as well

  Modified files:
    trunk/README.md