"While executing gem ... (Errno::EADDRNOTAVAIL)
     The requested address is not valid in its context. - connect(2) for "0.0.0.0" port 53"

Basically, its only that your requested address is not valid at that time on a particular port. Today, I have also having the same problem in installing ruby and jekyll framework and i search it and i did'nt get anything and then i tried same same code in my command prompt in my windows operating system. after trying 6 times in 7th time code will automatically run and the jekyll framework installed.
So, i just wanna say try same code again and again you will got it.
Have good day.