Fixed remove button crash (closes #2)
Fix label
Graph changes

Legend is updated as soon as scope starts
Hide legend until scope is started
Changed datetime in X-axis to seconds (more readable)
Removed graph title
Changed unit of x-axis values (fixes #3)

Changed unit of x-axis values(internally milliseconds, x-axis labels in
second, minutes or hours)
Added dynamic scaling (unit change) of x-axis
Removed some debug output
Immediately start communication