Don't allow writing second register of 2 register long numbers #19
Description
When writing data to the modbus it is possible to enter text in the second half of the register displayed which results in the value written to write half of two different pairs of registers.
For example, when displaying floats, it is possible to write to register "1" which results in the value of the 0,1 pair and 2,3 pair being affected since the value is written to register 1 and 2. This should either be prevented or made to write to register 0,1.
