Lee and Rob updated outlier handling

- trailed a manual logical statement that looked for values that were
+- 1 std of their neighbour. This wasn't great so we moved on to
building a code that asks the users to choose which points they wish to
include in the analysis.
- next step is to combine the two so that the code runs automatically
when the fit is good and when it encounters and error or a bad fit it
will ask the user to choose which points to discard.

Lots left to do.