Christopher Thomas

Add option to do signal analysis in returns space

1

Resolves #144 by adding a variable to flag whether we want to do signal analysis in returns space instead of on the levels.

signals.R -- post.signal.returns function returns only difference in levels, not returns

3

### Description As in title -- when using the apply.paramset.signal.analysis function, which calls on the post.signal.returns function, we're seeing the changes in the level, rather than returns. ### Expected behavior...