Merge pull request #46 from michaelhukun/master

pull
Merge pull request #47 from michaelhukun/master

pull
Merge pull request #48 from michaelhukun/master

pull
delete files
bond csv
bond
bond
Bond
bond curve
Bond Curve
Bond test
discount curve to string
coupon rate
Merge pull request #8 from Neoracle/master

sync with jianwei