[SSGPLVM] support linear kernel with ARD off
[SSGPLVM] support linear kernel with ARD off

fivejjs/GPy,jameshensman/GPy,mikecroucher/GPy,befelix/GPy,strongh/GPy,avehtari/GPy,maaskola/GPy,dhhjx880713/GPy,maaskola/GPy,buntyke/GPy,buntyke/GPy,avehtari/GPy,buntyke/GPy,ptonner/GPy,PredictiveScienceLab/GPy,Dapid/GPy,beckdaniel/GPy,mikecroucher/GPy,fivejjs/GPy,SheffieldML/GPy,esiivola/GPYgradients,strongh/GPy,AlexGrig/GPy,Dapid/GPy,dhhjx880713/GPy,mikecroucher/GPy,buntyke/GPy,dhhjx880713/GPy,jameshensman/GPy,avehtari/GPy,esiivola/GPYgradients,AlexGrig/GPy,jameshensman/GPy,AlexGrig/GPy,maaskola/GPy,avehtari/GPy,TianpeiLuke/GPy,ysekky/GPy,esiivola/GPYgradients,SheffieldML/GPy,ptonner/GPy,Dapid/GPy,gusmaogabriels/GPy,maaskola/GPy,jameshensman/GPy,ptonner/GPy,mikecroucher/GPy,TianpeiLuke/GPy,ptonner/GPy,esiivola/GPYgradients,AlexGrig/GPy,beckdaniel/GPy,beckdaniel/GPy,Dapid/GPy,ysekky/GPy,ysekky/GPy,befelix/GPy,TianpeiLuke/GPy,PredictiveScienceLab/GPy,befelix/GPy,beckdaniel/GPy,gusmaogabriels/GPy,PredictiveScienceLab/GPy,fivejjs/GPy,SheffieldML/GPy,befelix/GPy,dhhjx880713/GPy,PredictiveScienceLab/GPy,SheffieldML/GPy,ysekky/GPy,gusmaogabriels/GPy,strongh/GPy