plotting works, only demo is tested

switching readers when demo is enabled breaks demo

integrated almost all code to to use new Stream class, plotting doesn't work yet

building works, needs major cleanup

reworked DataFormatPanel for new design, not tested

dependency and direct interactions with ChannelManager and DataRecorder is removed

fix issue #15 snapshots not loading completely in some cases

I think this is a buffering issue caused by use of QFile.canReadLine function.
Note that loaded portion of the file was approximately 16k.

fix qtcolorwidgets to a working version

There has been some updates to build structure of the qtcolorwidgets. This is
the quickest way to get things working again. This should have been done in the
first place.

samplepack class for stream and basic test

note: test files are copied from "longmem" branch, be careful when merging

cache bounding rectangle instead of re-calculating at every reading

improves performance significantly for big buffers

don't allow xmin >= xmax

it breaks the plot because of newly implemented setrectofinterest