Added support for choosing the rate at the which the location is fetched based on distance.

[cybersokari]

Added distanceFilter from distanceFilter in iOS.
Added distanceFilter from smallestDisplacement in Android
Added isMock from isFromMockProvider variable in Android, iOS is always false

[aliciasteiman]

I'm using this plugin for an app for runners and being able to accurately track distance (in the background) is a huge component of the app. Right now I have the distance filter set to its default value 0, but I'm noticing that I'm collecting close to 2000 waypoints for a single run. Every time a new waypoint is added, I increase a variable "distance" by using the Geolocator.distanceBetween(waypoint, waypoint) function so that I can display dynamic distance tracking to the user as they run. However, this distance is wayyyy overestimated. I'm wondering if decreasing the number of waypoints will help, but it's a little unclear what distanceFilter represents. For example, if I set distanceFilter to 10 what does that mean?

[Almoullim]

@aliciasteiman

distanceFilter

iOS:

The minimum distance (measured in meters) a device must move horizontally before an update event is generated.

Android:

The minimum displacement between location updates in meters