Change generated document application name

[lafriks]

Currently it's constant Go Excelize with no way to change it.

excelize/templates.go

Line 26 in 471f4f8

const templateDocpropsApp = `<Properties xmlns="http://schemas.openxmlformats.org/officeDocument/2006/extended-properties" xmlns:vt="http://schemas.openxmlformats.org/officeDocument/2006/docPropsVTypes"><TotalTime>0</TotalTime><Application>Go Excelize</Application></Properties>`

[xuri]

Thanks for your issue. I have added two APIs: SetAppProps and GetAppProps to support set and get document application properties, please upgrade to the master branch code, and this feature will released in the next version.

[lafriks]

Thanks for prompt response, great library 👍