Added LU to CPU
Added LU to CPU

pentschev/arrayfire,ghisvail/arrayfire,bkloppenborg/arrayfire,merlin-ext/arrayfire,ghisvail/arrayfire,hshindo/arrayfire,umar456/arrayfire,bkloppenborg/arrayfire,asifmadnan/arrayfire,jramapuram/arrayfire,9prady9/arrayfire,Keno/arrayfire,pombredanne/arrayfire,umar456/arrayfire,pentschev/arrayfire,asifmadnan/arrayfire,linan7788626/arrayfire,linan7788626/arrayfire,Keno/arrayfire,pentschev/arrayfire,shehzan10/arrayfire,HolyGeneralK/arrayfire,umar456/arrayfire,victorv/arrayfire,marbre/arrayfire,victorv/arrayfire,victorv/arrayfire,mrgloom/arrayfire,HolyGeneralK/arrayfire,jramapuram/arrayfire,arrayfire/arrayfire,bkloppenborg/arrayfire,9prady9/arrayfire,unbornchikken/arrayfire,victorv/arrayfire,arrayfire/arrayfire,hshindo/arrayfire,shehzan10/arrayfire,pombredanne/arrayfire,merlin-ext/arrayfire,pombredanne/arrayfire,mrgloom/arrayfire,asifmadnan/arrayfire,asifmadnan/arrayfire,munnybearz/arrayfire,umar456/arrayfire,arrayfire/arrayfire,merlin-ext/arrayfire,unbornchikken/arrayfire,hshindo/arrayfire,linan7788626/arrayfire,unbornchikken/arrayfire,jramapuram/arrayfire,jramapuram/arrayfire,9prady9/arrayfire,HolyGeneralK/arrayfire,pentschev/arrayfire,arrayfire/arrayfire,Keno/arrayfire,ghisvail/arrayfire,9prady9/arrayfire,hshindo/arrayfire,munnybearz/arrayfire,marbre/arrayfire,munnybearz/arrayfire,shehzan10/arrayfire,pombredanne/arrayfire,linan7788626/arrayfire,marbre/arrayfire,mrgloom/arrayfire,HolyGeneralK/arrayfire,unbornchikken/arrayfire,marbre/arrayfire,mrgloom/arrayfire,ghisvail/arrayfire,bkloppenborg/arrayfire,shehzan10/arrayfire,merlin-ext/arrayfire,Keno/arrayfire