fix issue with python 2.6.6
remove filter for min_loan_amt for FHA-HB types
remove unnecessary bit
Merge pull request #14 from fna/fix-python-2.6.6-issue

Fix comparison Decimal to float
Merge pull request #13 from fna/issue-with-min-loan-amt-for-fha-hb

Change rate_query for FHA-HB types
modify tests
Merge pull request #15 from fna/modify-countylimits-test

Modify tests