App should support export configurations into json/xml files

[p-z-l]

This allows us to share configs with other teammates to make sure that the code format stays the same throughout the entire project.

Also, I think multiple profiles could be helpful as well.

[ruiaureliano]

I will set a custom file for configuration and rules, probably

.xsfconfig
.xsfrules

thanks @p-z-l

[ruiaureliano]

It now open and save .xsfconfig and .xsfrules files