Give useful messages on submitting log

[renlok]

• If a exercise is added with no sets give a warning
• if a exercise is new say it is new instead of saying you hit a pr
• if an exercise has been assumed to be a time give a warning to the user + instructions to change it
• if users first log is units are inputted guess their default unit then ask if it correct

[renlok]

• if bodyweight exercises used but no bodyweight set give a warning

[renlok]

• If a exercise is added with no sets give a warning - done
• if a exercise is new say it is new instead of saying you hit a pr - done
• if an exercise has been assumed to be a time give a warning to the user + instructions to change it - done
• if bodyweight exercises used but no bodyweight set give a warning - done

Just need to add:

• if users first log is units are inputted guess their default unit then ask if it correct