Upgrade jmake to version that works with java 1.5+
Upgrade jmake to version that works with java 1.5+

This upgrades from 1.3.8-7 to 1.3.8-8 - no functional changes,
just a release with java 1.5+ compatible classfiles.

See this issue for details: https://github.com/pantsbuild/jmake/issues/13

Testing Done:
CI went green here: https://travis-ci.org/pantsbuild/pants/builds/47557498

Bugs closed: 960

Reviewed at https://rbcommons.com/s/twitter/r/1628/

kslundberg/pants,jtrobec/pants,pgroudas/pants,slyphon/pants,dbentley/pants,ericzundel/pants,pombredanne/pants,landism/pants,Gabriel439/pants,baroquebobcat/pants,pombredanne/pants,ity/pants,foursquare/pants,gmalmquist/pants,TansyArron/pants,Gabriel439/pants,areitz/pants,landism/pants,tdyas/pants,UnrememberMe/pants,manasapte/pants,dgomez10/xanon,qma/pants,megaserg/pants,jsirois/pants,jtrobec/pants,megaserg/pants,mateor/pants,dgomez10/xanon,di0spyr0s/pants,ity/pants,wisechengyi/pants,kwlzn/pants,ericzundel/pants,jtrobec/pants,dturner-tw/pants,Gabriel439/pants,pantsbuild/pants,scode/pants,landism/pants,UnrememberMe/pants,dgomez10/xanon,sid-kap/pants,jessrosenfield/pants,jtrobec/pants,qma/pants,pombredanne/pants,pantsbuild/pants,kwlzn/pants,peiyuwang/pants,gmalmquist/pants,sid-kap/pants,UnrememberMe/pants,dgomez10/xanon,sameerparekh/pants,tdyas/pants,ericzundel/pants,jtrobec/pants,jessrosenfield/pants,dgomez10/xanon,tejal29/pants,areitz/pants,tdyas/pants,slyphon/pants,megaserg/pants,twitter/pants,landism/pants,mateor/pants,baroquebobcat/pants,dgomez10/xanon,wisechengyi/pants,scode/pants,baroquebobcat/pants,kwlzn/pants,fkorotkov/pants,pombredanne/pants,laurentgo/pants,laurentgo/pants,kslundberg/pants,benjyw/pants,gmalmquist/pants,15Dkatz/pants,cevaris/pants,kslundberg/pants,benjyw/pants,megaserg/pants,TansyArron/pants,laurentgo/pants,lahosken/pants,scode/pants,jessrosenfield/pants,benjyw/pants,di0spyr0s/pants,gmalmquist/pants,UnrememberMe/pants,jessrosenfield/pants,tdyas/pants,sid-kap/pants,UnrememberMe/pants,sid-kap/pants,Gabriel439/pants,ity/pants,landism/pants,kslundberg/pants,lahosken/pants,kwlzn/pants,qma/pants,ericzundel/pants,wisechengyi/pants,Gabriel439/pants,dgomez10/xanon,fkorotkov/pants,dturner-tw/pants,sid-kap/pants,dbentley/pants,gmalmquist/pants,di0spyr0s/pants,Gabriel439/pants,15Dkatz/pants,areitz/pants,gmalmquist/pants,wisechengyi/pants,manasapte/pants,dturner-tw/pants,pantsbuild/pants,wisechengyi/pants,sid-kap/pants,digwanderlust/pants,sameerparekh/pants,areitz/pants,ity/pants,tdyas/pants,cevaris/pants,baroquebobcat/pants,baroquebobcat/pants,laurentgo/pants,Gabriel439/pants,jessrosenfield/pants,wisechengyi/pants,landism/pants,peiyuwang/pants,ity/pants,UnrememberMe/pants,di0spyr0s/pants,UnrememberMe/pants,foursquare/pants,jessrosenfield/pants,dgomez10/xanon,qma/pants,kwlzn/pants,lahosken/pants,TansyArron/pants,foursquare/pants,pombredanne/pants,peiyuwang/pants,wisechengyi/pants,dbentley/pants,dbentley/pants,dturner-tw/pants,tdyas/pants,mateor/pants,15Dkatz/pants,manasapte/pants,pombredanne/pants,lahosken/pants,foursquare/pants,sid-kap/pants,mateor/pants,foursquare/pants,benjyw/pants,dgomez10/xanon,UnrememberMe/pants,landism/pants,digwanderlust/pants,cevaris/pants,pantsbuild/pants,foursquare/pants,pantsbuild/pants,kwlzn/pants,slyphon/pants,tdyas/pants,twitter/pants,cevaris/pants,jtrobec/pants,pgroudas/pants,TansyArron/pants,baroquebobcat/pants,slyphon/pants,twitter/pants,pgroudas/pants,manasapte/pants,TansyArron/pants,dturner-tw/pants,twitter/pants,digwanderlust/pants,kslundberg/pants,qma/pants,benjyw/pants,dturner-tw/pants,jessrosenfield/pants,twitter/pants,slyphon/pants,gmalmquist/pants,tejal29/pants,baroquebobcat/pants,tejal29/pants,foursquare/pants,mateor/pants,dgomez10/xanon,ericzundel/pants,sameerparekh/pants,15Dkatz/pants,areitz/pants,cevaris/pants,lahosken/pants,manasapte/pants,mateor/pants,landism/pants,digwanderlust/pants,pgroudas/pants,ericzundel/pants,fkorotkov/pants,pgroudas/pants,laurentgo/pants,cevaris/pants,pantsbuild/pants,slyphon/pants,areitz/pants,twitter/pants,twitter/pants,laurentgo/pants,wisechengyi/pants,qma/pants,kslundberg/pants,cevaris/pants,peiyuwang/pants,fkorotkov/pants,lahosken/pants,tdyas/pants,dbentley/pants,pombredanne/pants,qma/pants,tejal29/pants,di0spyr0s/pants,megaserg/pants,manasapte/pants,fkorotkov/pants,peiyuwang/pants,scode/pants,scode/pants,digwanderlust/pants,ericzundel/pants,UnrememberMe/pants,TansyArron/pants,di0spyr0s/pants,twitter/pants,foursquare/pants,peiyuwang/pants,sameerparekh/pants,dgomez10/xanon,jsirois/pants,dbentley/pants,baroquebobcat/pants,pgroudas/pants,megaserg/pants,15Dkatz/pants,benjyw/pants,foursquare/pants,scode/pants,digwanderlust/pants,baroquebobcat/pants,peiyuwang/pants,scode/pants,dturner-tw/pants,pantsbuild/pants,ity/pants,mateor/pants,twitter/pants,fkorotkov/pants,lahosken/pants,15Dkatz/pants,manasapte/pants,mateor/pants,kwlzn/pants,ity/pants,ericzundel/pants,wisechengyi/pants,sameerparekh/pants,15Dkatz/pants,peiyuwang/pants,lahosken/pants,jtrobec/pants,di0spyr0s/pants,fkorotkov/pants,benjyw/pants,sameerparekh/pants,tejal29/pants,areitz/pants,sameerparekh/pants,TansyArron/pants,dbentley/pants,fkorotkov/pants,tdyas/pants,15Dkatz/pants,jsirois/pants,megaserg/pants,slyphon/pants,kslundberg/pants