scicam coords and val displayed under canvas. (readout attr in displayed_image; scicam_gl definition in status_stream print errors in other pages but does not affect stream)

DysplayImage class in WebGLDrawer to read image values from canvas (incomplete, checkout if not working). WIP

read cursor position in canvas, plot serRectangle coordinates to read image pixels and vals, still WIP

telescope and offset tab : read options from schema.  Tel offset api works. Added unit measure to coord and offsets. OBJNAME status info in tel

Scicam visualization: scicam_gl declared in tel, no more in form-actions, scicam socket client in status-stream, no more in form-actions

webgl-drawer takes drawing params as attributes, fast scaling and shift works. (Issues in loading large images)