Status Header File
PS 4824 adpations: setDataBuffer() & setChannel functions

Added additional voltage ranges in channel range codes

Minor additions in the constants definition

Added setDataBuffer function for streaming mode
added run_streaming function of ps4000

function runs but results in error: PICO_INVALID_SAMPLERATIO
dunno why yet.
working run_streaming example

Problem solved,
downSampleRatio was 0, must be 1 and downSample RatioMode has to be set
0!

Used bufferlength is now set in set_data_buffer and automatically used
in run_streaming (must be same size)

NOTE: this code only works for Channel A! Adoption is needed for all
Channel setup
Merge pull request #3 from mischele/master

Basic Functions added to picoscope4000: setChannel & setDataBuffer