if part name is exact then should return the exact part

[JMante1]

It is really annoying that if you type in an exact BBa_.... it is not the first result.

[cjmyers]

This issue relates to #28. Namely, what is happening is PageRank score is shifting some matches above the exact match. This is done because it allows for mis-spellings to still be picked up. Case in point, if you search BBa_F2260 you get the more popular result of BBa_F2620 reflecting that you likely mis-typed. That being said, it may be worth experimenting with the weightings to see if there is a better mix that gives more expected results. Closing this issue, since it is effectively a duplicate of #28.