doc(readme): install client deps with jspm
doc(readme): install client deps with jspm

Running tests instructions did not list jspm command

bfil/validation,milunka/validation,manuel-guilbault/aurelia-validation,manuel-guilbault/aurelia-validation,Bcpoole/validation,DavidBLynch/validation,DaveGee/validation,valichek/validation,mbroadst/validation,mbroadst/validation,RichTeaTime/validation,santosh-suresh/validation,Zensavona/validation,JeroenVinke/validation,JeroenVinke/aurelia-validation-update,PWKad/validation,vulvulune/validation,hitesh97/validation,RichTeaTime/validation,aurelia/validation,PWKad/validation,JeroenVinke/validation,JeroenVinke/validation-fix,DaveGee/validation,ericIMT/validation,Bcpoole/validation,milunka/validation,bellstrand/validation,aurelia/validation,charlespockert/validation,vulvulune/validation,ericIMT/validation,jdanyow/validation