set default name to export if empty filename

[estellepicq]

If provided filename is an empty string:

• Before: get file 'csv'
• Now: set value to 'export' and get file 'export.csv'

Tried to pass it as default value (...public static data( filename: string = 'export',....) but empty strings are not undefined values.

[LCluber]

it would me more efficient to put your code after the data check :

if (!Is.object(data[0]) && !Is.json(data[0])) {
return false;
}

[estellepicq]

Code moved after data check as requested.

Off topic: my IDE points out this error in tsconfig.json: 'Cannot write file "[...]/src/ts/build/es6/convert.d" because it would overwrite input file'