Results 3 issues of Marcus

this error occurs when running 'output_sample.py', and I found that though there are some variable scopes when building the network in 'out_model.py', such as ` with tf.variable_scope('SegLayer'): mod = M.Model(feature)...

Add an optional Boolean argument `--loopminer` to `mine` command. When set to `false`, the miner will exit after completing one mining process.