Refactor code into WriteHeader
Move SheetWriter code to end of file
Split TemplateSheet into start, rows and end sections
Add large.go to test with 100000 rows
Move large example to the right place
Add to gitignore
Move {{end}} into the right template section
Refactor into SheetWriter
Fix formatting
Work on multiple calls to WriteRows
Use fork of xlsx in large test
Rows are now constructed individually, allowing for multiple calls to WriteRows to create a valid xlsx file
Edit large example
Work towards writing multiple sheets; the sheet can now be renamed
Remove unnecesary declaration
Made it so that the API isn't broken
Remove the now unnecessary TemplateSheetRows
Change sheet Write function to WriteHeader
Change example to conform to API
Automatically close SheetWriters when they are done with