Fix LCA(i,i) = i

[fbreitwieser]

Currently, a BLAST result with entries with the same taxonomy IDs gets the parent taxonomy ID as result.

For example, the following line is for the species Papiine herpesvirus 2:

Q_1        gi|116260100|gb|ABJ91141.1|     100.00  56      0       0       1       56      1       56      2e-27     104

However, when I duplicate this line (or just have another result with the same taxID), the result is given as genus Simplexvirus:

Q_1        gi|116260100|gb|ABJ91141.1|     100.00  56      0       0       1       56      1       56      2e-27     104
Q_1        gi|116260100|gb|ABJ91141.1|     100.00  56      0       0       1       56      1       56      2e-27     104

This commit fixes that.