Populate readme a bit

README.md

+# tabor_control
+
+This package provides a thin abstraction over SCPI controlled Tabor Electronics AWGs.
+
+ - Discovery of such devices in the networkl 
+ - Initialization of visa sessions with reasonable defaults
+ - Binary up- and download of waveform segments and sequencing tables
+ - Device properties like total memory and sequence restrictions
+ - Workaround some quirks if a simulator is used
+ - Basic object-oriented interface to the above