Class ChemicalSearch

Given a SMILES string (and a limit on the results size), returns
the most similar fingerprints known by the fingerprint server 
(specified in the Env.py file) as well as a similarity score
of each found fingerprint to the original search string.

Additional methods include an option to actually retrieve the 
database information for the chemicals with those fingerprints
(while still keeping the similarity scores).

Input: 
- searchString:  
    SMILES format of a molecule or component to search for similarity by.
- maxResults:  
    Maximum number of similar fingerprints to return
- resultsStart:  
    First result index to take out of the full possible results set

Output:
- resultsFile:
    Output is the the fingerprint strings found to be most similar to the 
    search criteria.  Alternatively, an option allows for the return of
    the full-database information for the chemicals with those fingerprints.

    Redirection to stdout possible by specifying the filename "-"

Given a ChemicalSearchModel, see if it has a 
similarMols list of OEMolBase objects, then find all of the 
chemical database records that match all of those critiera
and return that data, including the supplementary search
information like similarityScores.

If not, just look for other search criteria in the model and find chemicals
by those criteria and return the same data (minus the similarityScore, etc.).

Example Usage:

from CHEM.Common.ChemicalSearch import ChemicalSearch;
from CHEM.Common.Model import ChemicalSearchModel;
from CHEM.Common.Util import molBySmiles;

mol = molBySmiles("c1ccccc1N=C=O");
chemicalSearch = ChemicalSearch()

chemicalQuery = ChemicalSearchModel();
chemicalQuery.maxResults = 10;
chemicalQuery.similarityThreshold = 0.5;
chemicalQuery.addSimilarMol(mol);

resultChemicalModels = chemicalSearch.findChemicals(chemicalQuery);

for chemical in resultChemicalModels:
    print chemical["can_smiles"];