Add Save() and IsSaved/IsModified to FileContext API

[nightroman]

Is there any method to save a file opened in the editor? Ideally, to save if it
is modified. If there is a way to check the modified state then I am just
looking for a way to save.

The context. I am working on Invoke-TaskFromVSCode, similar to Invoke-TaskFromISE.
The script with tasks should be saved before invoking the current task from it.

In ISE it looks like

$file = $psISE.CurrentFile
if (!$file.IsSaved) {
    $file.Save()
}

[nightroman]

Here is the current Invoke-TaskFromVSCode.ps1. For now it requires a user to save the current build script manually before invoking a task. It would be very useful to make this saving automatic.

[daviwil]

Hey Roman, I can definitely add a 'Save' function and I believe I should be able to add an 'IsModified' field to show whether the file hasn't yet been saved. I will try to get this in for the 0.7.0 release which should be out in the second half of July once I'm back from vacation.