Add Features to Sentencevectors

[oborchers]

[ ] Sentencevectors:
Global:
[ ] Remove normalized vector files and replace with NN
ANN: --> (Annoy, with Option for Google ScANN?)
[ ] Only construct index when when calling most_similar method
[ ] Logging of index speed
[ ] Save and load of index
[ ] Assert that index and vectors are of equal size
[ ] Paramters must be tunable afterwards
[ ] Method to reconstruct index
[ ] How does the index saving comply with SaveLoad?
[ ] Write unittests?
Brute:
[ ] Keep access to default method
[ ] Make ANN Search the default?! --> Results?
[ ] Throw warning for large datasets for vector norm init
[ ] Maybe throw warning if exceeds RAM size of the embedding + normalization
Other:
[ ] L2 Distance
[ ] L1 Distance
[ ] Correlation (Power Score Correlation?)
[ ] Lookup-Functionality (via defaultdict)
[ ] Get vector: Not really memory friendly
[ ] Show which words are in vocabulary
[ ] Asses empty vectors (via EPS sum)
[ ] Z-Score Transformation from Power-Means Embedding? --> Benefit?