Number crusher class for short URL's

This class crushes numbers into shorter values.

Since I bought `ytm.li`, short url's to video's could be like `ytm.li/v/o2wu`

Video ID | Crushed | Reverted | Even | Length profit
--- | --- | --- | --- | ---
5 | 5 | 5 | 1 | 0
57 | V | 57 | 1 | 1
572 | 9e | 572 | 1 | 1
5729 | 1up | 5729 | 1 | 1
57295 | eU7 | 57295 | 1 | 2
572957 | 2p3f | 572957 | 1 | 2
5729574 | o2wu | 5729574 | 1 | 3
57295744 | 3SpeU | 57295744 | 1 | 3
572957443 | CM4p5 | 572957443 | 1 | 4
5729574438 | 6fKI2W | 5729574438 | 1 | 4
57295744381 | 10xx6tn | 57295744381 | 1 | 4
572957443817 | a5pl2JP | 572957443817 | 1 | 5
5729574438175 | 1CS5oroj | 5729574438175 | 1 | 5
57295744381759 | ggIRWpVd | 57295744381759 | 1 | 6
572957443817596 | 2CHeHqbec | 572957443817596 | 1 | 6
5729574438175967 | qeYn0dOi3 | 5729574438175967 | 1 | 7