Distance missing from Save workout

[SeanDunford]

Background

Save Workout did not include distance which is an odd api choice because fetch workout does include distance. For my own personal needs adding distance to workout saving was necessary and i imagine it will be valuable to other users as well. I did mention a notice of missing permissions somewhere in the code but i tested this code and it works as is. Modeled it after the way calories and intensity are optionally added into the save workout payload.

Mention in comments about permission restriction
https://github.com/StasDoskalenko/react-native-google-fit/blob/master/android/src/main/java/com/reactnative/googlefit/ActivityHistory.java#L390

    // distance scope is missing here due to permission restriction
    // will be added in the future while distance is also available from saveWorkout()

Proposed Solution

Add distance in a similar manner to calories/intensity

[SeanDunford]

PR:
#356