Further improvements for the real experiments

1) Added the inter* phases to the behav and fmri sessions. Also added
pract1 and pract2 phases to the fmri sessions.

These are optional sessions that can be bypasssed by answering "no" in the question prompt.

2) Added the center-target lines to the intensity and rate columns of the
user visual feedback window.

3) Reorganized the order of the three columsn in the user visual feedback
window to make it more logical.

4) Matched the rate in the N and R conditions.