Fixed
* Improved caching of lower-bound for DTW
The DTW subsequence search implementation has been improved by caching
DTW lower-bound information for repeated calls with the same
subsequece. This slightly increases the memory requirement, but can
give significantly improved performance under certain circumstances.
* Allow shapelet information to be extracted
A new attribute `ts_info` is added to `Shapelet` (which is accessible
from `tree.root_node_.shapelet`). `ts_info` returns a tuple
`(ts_index, ts_start, length)` with information about the index (in
the `x` used to fit, `fit(x, y)`, the model) and the start position of
the shapelet. For a shapelet tree/forest fit on `x` the shapelet in a
particular node is given by `x[ts_index, ts_start:(ts_start + length)]`.