start date and end date added to production order doctype
Calender and gantt chart view added for production order doctype
Filters added
data type of start_date and end_date changed to datetime
fix - validations added for auto fetch of cost center
Merge pull request #2312 from neilLasrado/production-calender-sync

Production calender sync
Merge pull request #2356 from neilLasrado/cost-center-undefined-error-fix

fix - validations added for auto fetch of cost center
 FIX validate-bom wrong condition
fixed
Merge pull request #2349 from neilLasrado/validate-bom-fix

 FIX validate-bom wrong condition
Material Issue added to Material Request Type
mapper added, type 'Transfer' renamed to 'Material Transfer', patch added
required modifications done