Added location finding notebook

[ashandonay]

I added the location finding problem notebook in the examples folder. The notebook includes the 1D space and 2D space problems with one and two sources in each case.

[dkirkby]

This is looking good! Here are some notes on the first section (1D space, 1 source):

• You redefine ngrid in many cells, but never used this value later. I would just put the constants directly into the Grid(...) constructors.
• Let's add b and m as constants in the parameter Grid, so they could be allowed to vary, instead of treating them like hyperparams like sigma_s.
• Your plot of the marginal prob indicates that the coverage of the s grid should be expanded to avoid truncation at the edges.
• Move the legend to the upper right in the Prior + Posterior plot.
• spelling: "multi-modal"

[dkirkby]

Referring to the latest changes, L=10 is useful to define once since you use it in several cells (unlike ngrid).