Merge pull request #30 from adityaduggal/master

FIxes for Float field problem
Added validations to Sales Invoice to DISALLOW SI from only SO or DN
-Now if either of SO or DN is mentioned then SI wont be allowed
-This effectively means that either you can make SI for SO and DN but not for one only.
Merge pull request #31 from adityaduggal/master

Added validations to Sales Invoice to DISALLOW SI from only SO or DN
Minor changes to Centre Drill range
Merge pull request #32 from adityaduggal/master

Minor changes to Centre Drill range
Added TIN Coating option for rectangular HSS
Merge pull request #18 from frappe-apps/master

Old Merge
Merge pull request #19 from adityaduggal/master

Merge