Fix "installing bash completion" instructions
Fix "installing bash completion" instructions

The scripts are copied/linked into a _directory_, not a file.
The two directories are the default locations for bash completion extensions.

Signed-off-by: Harald Albers <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@albersweb.de>

docker/docker.github.io,SvenDowideit/machine,pottava/machine,skatsuta/machine,londoncalling/docker.github.io,londoncalling/docker.github.io,phiroict/docker,zchee/machine,shubheksha/docker.github.io,tpires/machine,aduermael/docker.github.io,tyrken/machine,johnstep/docker.github.io,menglingwei/denverdino.github.io,ibuildthecloud/machine,wzymaster/machine,JimGalasyn/docker.github.io,jmelis/machine,JimGalasyn/docker.github.io,alexisbellido/docker.github.io,jzwlqx/denverdino.github.io,errordeveloper/machine,denverdino/denverdino.github.io,shubheksha/docker.github.io,pottava/machine,JimGalasyn/docker.github.io,gdevillele/docker.github.io,ibuildthecloud/machine,docker/machine,JimGalasyn/docker.github.io,voutilad/machine,robertbreker/machine,sanscontext/docker.github.io,denverdino/denverdino.github.io,gdevillele/docker.github.io,thaJeztah/docker.github.io,bdwill/docker.github.io,robvanmieghem/machine,shin-/docker.github.io,faijaz/docker-machine,londoncalling/docker.github.io,robvanmieghem/machine,JohnKDay/machine,exoscale/docker-machine,jmelis/machine,jeffellin/machine,denverdino/docker.github.io,SvenDowideit/machine,rillig/docker.github.io,denverdino/machine,joeuo/docker.github.io,otherjason/machine,phiroict/docker,otherjason/machine,menglingwei/machine,JohnKDay/machine,LuisBosquez/docker.github.io,anweiss/docker.github.io,docker-zh/docker.github.io,londoncalling/docker.github.io,aduermael/docker.github.io,ppadala/machine,jmelis/machine,LuisBosquez/docker.github.io,thaJeztah/docker.github.io,kunalkushwaha/machine,danix800/docker.github.io,xinxian0458/machine,jeanlaurent/machine,jsirois/machine,menglingwei/denverdino.github.io,joeuo/docker.github.io,menglingwei/machine,kacole2/machine,johnstep/docker.github.io,docker/machine,docker/docker.github.io,rillig/docker.github.io,alexisbellido/docker.github.io,flavio/machine,StackPointCloud/machine,errordeveloper/machine,phiroict/docker,kunalkushwaha/machine,joeuo/docker.github.io,zchee/machine,dgageot/machine,kunalkushwaha/machine,danix800/docker.github.io,docker-zh/docker.github.io,joaofnfernandes/docker.github.io,xinxian0458/machine,docker/docker.github.io,kacole2/machine,phiroict/docker,docker-zh/docker.github.io,larsla/machine,shubheksha/docker.github.io,troy0820/docker.github.io,pottava/machine,docker-zh/docker.github.io,docker/docker.github.io,menglingwei/denverdino.github.io,tpires/machine,shin-/docker.github.io,bdwill/docker.github.io,aduermael/docker.github.io,johnstep/docker.github.io,ppadala/machine,tyrken/machine,menglingwei/machine,moxiegirl/machine,bdwill/docker.github.io,faijaz/docker-machine,tpires/machine,johnstep/docker.github.io,denverdino/machine,exoscale/docker-machine,miqui/machine,docker-zh/docker.github.io,StackPointCloud/machine,danix800/docker.github.io,bdwill/docker.github.io,sanscontext/docker.github.io,londoncalling/machine,dweomer/docker-machine,sebadiaz/machine,gdevillele/docker.github.io,sebadiaz/machine,shin-/docker.github.io,errordeveloper/machine,joaofnfernandes/docker.github.io,jsirois/machine,denverdino/denverdino.github.io,wzymaster/machine,menglingwei/denverdino.github.io,bdwill/docker.github.io,miqui/machine,skatsuta/machine,anweiss/docker.github.io,miqui/machine,tyrken/machine,joaofnfernandes/docker.github.io,soleo/machine,jeffellin/machine,shin-/docker.github.io,faijaz/docker-machine,LuisBosquez/docker.github.io,jeanlaurent/machine,Herbis/machine,thaJeztah/docker.github.io,kacole2/machine,thaJeztah/machine,shubheksha/docker.github.io,flavio/machine,jeanlaurent/machine,jsirois/machine,LuisBosquez/docker.github.io,denverdino/docker.github.io,moxiegirl/machine,jeffellin/machine,bgokden/machine,JohnKDay/machine,shin-/docker.github.io,londoncalling/machine,robertbreker/machine,sanscontext/docker.github.io,thaJeztah/machine,thaJeztah/docker.github.io,troy0820/docker.github.io,jzwlqx/denverdino.github.io,LuisBosquez/docker.github.io,robertbreker/machine,anweiss/docker.github.io,docker/docker.github.io,denverdino/docker.github.io,denverdino/docker.github.io,joeuo/docker.github.io,larsla/machine,gdevillele/docker.github.io,sanscontext/docker.github.io,skatsuta/machine,sebadiaz/machine,denverdino/denverdino.github.io,thaJeztah/machine,thaJeztah/docker.github.io,BSWANG/denverdino.github.io,bgokden/machine,troy0820/docker.github.io,Herbis/machine,rillig/docker.github.io,BSWANG/denverdino.github.io,ppadala/machine,alexisbellido/docker.github.io,StackPointCloud/machine,joaofnfernandes/docker.github.io,aduermael/docker.github.io,alexisbellido/docker.github.io,moxiegirl/machine,wzymaster/machine,soleo/machine,zchee/machine,jzwlqx/denverdino.github.io,phiroict/docker,danix800/docker.github.io,sanscontext/docker.github.io,dweomer/docker-machine,BSWANG/denverdino.github.io,troy0820/docker.github.io,joeuo/docker.github.io,bgokden/machine,dgageot/machine,anweiss/docker.github.io,xinxian0458/machine,denverdino/machine,jzwlqx/denverdino.github.io,londoncalling/docker.github.io,jzwlqx/denverdino.github.io,rillig/docker.github.io,denverdino/docker.github.io,soleo/machine,anweiss/docker.github.io,otherjason/machine,alexisbellido/docker.github.io,gdevillele/docker.github.io,robvanmieghem/machine,johnstep/docker.github.io,joaofnfernandes/docker.github.io,BSWANG/denverdino.github.io,voutilad/machine,denverdino/denverdino.github.io,menglingwei/denverdino.github.io,JimGalasyn/docker.github.io,shubheksha/docker.github.io,BSWANG/denverdino.github.io