Add .xls, .json, .csv export features.

[Otabek]

Issue type: feature request

Full issue message: Add .xls, .json, .csv export features. This is very helpful when creating apps that save data on user's PC. I think there should be extra features for adding, editing, exporting, removing and loading that type of files. User also should be able to load the data when app launches and export when exiting from the app. Also, if you add the feature of saving data in every givenTime(e.g: 5 mins), it would blow minds of people who're using this DB.

Issue author: @otabekoff(Otabek Sadiridinov)

[Samuel Wallace Assuncao]

export collection data as xls ? Yes that is very possible but it will require use of other dependency, I can look into it.