Basic server emulator

Emulator generates NCI values and allows to check graph work without server.
To switch on emulation mode just add in nci.html
    <script src='static/server_emulator.js'></script>
 after
   <script src='static/chart.js'></script>

Now there are 3 configurable options on the top of server_emulator.js file

NCI.Emulator.liveDataFrequency - how ofter will NCI values get to server
NCI.Emulator.dataAvailablePeriod  - the period of time from now for which emulator will generate data
NCI.Emulator.serverResponceDelay - emulates responce dalay (as emulator can responce imidiatly)