Add more cases in DefinieLinkUTest
Add more cases in DefinieLinkUTest

1. Reinserting the same definition doesn't raise an error
2. Inserting a definition with the same alias and a different body raise an error

Selameab/atomspace,rodsol/atomspace,AmeBel/atomspace,UIKit0/atomspace,inflector/atomspace,MarcosPividori/atomspace,yantrabuddhi/atomspace,misgeatgit/atomspace,rTreutlein/atomspace,yantrabuddhi/atomspace,ArvinPan/atomspace,MarcosPividori/atomspace,jswiergo/atomspace,AmeBel/atomspace,AmeBel/atomspace,AmeBel/atomspace,ArvinPan/atomspace,inflector/atomspace,printedheart/atomspace,virneo/atomspace,jswiergo/atomspace,yantrabuddhi/atomspace,UIKit0/atomspace,cosmoharrigan/atomspace,rTreutlein/atomspace,rTreutlein/atomspace,rodsol/atomspace,williampma/atomspace,virneo/atomspace,virneo/atomspace,williampma/atomspace,williampma/atomspace,printedheart/atomspace,cosmoharrigan/atomspace,MarcosPividori/atomspace,misgeatgit/atomspace,rohit12/atomspace,rohit12/atomspace,Selameab/atomspace,UIKit0/atomspace,rodsol/atomspace,williampma/atomspace,jswiergo/atomspace,Selameab/atomspace,misgeatgit/atomspace,jswiergo/atomspace,rTreutlein/atomspace,ArvinPan/atomspace,ceefour/atomspace,rTreutlein/atomspace,printedheart/atomspace,yantrabuddhi/atomspace,Selameab/atomspace,virneo/atomspace,rohit12/atomspace,printedheart/atomspace,ArvinPan/atomspace,cosmoharrigan/atomspace,rodsol/atomspace,ceefour/atomspace,AmeBel/atomspace,misgeatgit/atomspace,inflector/atomspace,rohit12/atomspace,cosmoharrigan/atomspace,UIKit0/atomspace,MarcosPividori/atomspace,yantrabuddhi/atomspace,misgeatgit/atomspace,inflector/atomspace,ceefour/atomspace,ceefour/atomspace,inflector/atomspace