[network] Correct error in "Full Example" (#2825)
[network] Correct error in "Full Example" (#2825)

* Correct error in "Full Example", Issue #548 in openhab-docs

-  Prepends `Thing` to `network:pingdevice:devicename...`
-  Deletes a few unnecessary trailing spaces
-  Changed `demo.Things` to `demo.things`

Signed-off-by: Brad Gilmer <9233b6f5388d6867a2a7be14d8b4ba53c86cfde2@gilmer.tv> (github: bgilmer77)

Snickermicker/openhab2,trokohl/openhab2-addons,pail23/openhab2-addons,Nebula83/openhab2-addons,theoweiss/openhab2,andiikaa/openhab2,tavalin/openhab2-addons,Mr-Eskildsen/openhab2-addons,Nebula83/openhab2-addons,aogorek/openhab2-addons,lewie/openhab2,Mr-Eskildsen/openhab2-addons,jarlebh/openhab2-addons,digitaldan/openhab2,clinique/openhab2,digitaldan/openhab2,gerrieg/openhab2,tavalin/openhab2-addons,Nebula83/openhab2-addons,trokohl/openhab2-addons,jarlebh/openhab2-addons,pail23/openhab2-addons,trokohl/openhab2-addons,Mr-Eskildsen/openhab2-addons,Snickermicker/openhab2,johannrichard/openhab2-addons,tavalin/openhab2-addons,sebmarchand/openhab2-addons,jarlebh/openhab2-addons,andiikaa/openhab2,lewie/openhab2,tavalin/openhab2-addons,trokohl/openhab2-addons,mvolaart/openhab2-addons,afuechsel/openhab2,JueBag/openhab2-addons,JueBag/openhab2-addons,pgfeller/openhab2-addons,dimalo/openhab2-addons,tavalin/openhab2-addons,aogorek/openhab2-addons,pgfeller/openhab2-addons,sebmarchand/openhab2-addons,mvolaart/openhab2-addons,Snickermicker/openhab2,Snickermicker/openhab2,gerrieg/openhab2,dimalo/openhab2-addons,johannrichard/openhab2-addons,andiikaa/openhab2,Jamstah/openhab2-addons,gerrieg/openhab2,gerrieg/openhab2,aogorek/openhab2-addons,johannrichard/openhab2-addons,pgfeller/openhab2-addons,Mr-Eskildsen/openhab2-addons,tavalin/openhab2-addons,aogorek/openhab2-addons,pail23/openhab2-addons,clinique/openhab2,mvolaart/openhab2-addons,dimalo/openhab2-addons,hillmanr/openhab2-addons,hillmanr/openhab2-addons,dimalo/openhab2-addons,theoweiss/openhab2,digitaldan/openhab2,jarlebh/openhab2-addons,jarlebh/openhab2-addons,trokohl/openhab2-addons,afuechsel/openhab2,aogorek/openhab2-addons,johannrichard/openhab2-addons,Jamstah/openhab2-addons,pail23/openhab2-addons,johannrichard/openhab2-addons,clinique/openhab2,aogorek/openhab2-addons,clinique/openhab2,JueBag/openhab2-addons,Mr-Eskildsen/openhab2-addons,theoweiss/openhab2,Jamstah/openhab2-addons,andiikaa/openhab2,jarlebh/openhab2-addons,pgfeller/openhab2-addons,afuechsel/openhab2,trokohl/openhab2-addons,digitaldan/openhab2,lewie/openhab2,theoweiss/openhab2,dimalo/openhab2-addons,pgfeller/openhab2-addons,pail23/openhab2-addons,hillmanr/openhab2-addons,sebmarchand/openhab2-addons