As a user I want to parse names with years like 1888/89

[dimus]

created by @dimus at https://gitlab.com/gogna/gnparser/-/issues/81

Examples of such names

[WARN] [2020-05-06 10:24:56] Filtered Scientific Name `Macroplectra unicolor Moore, 1858/59` to `Macroplectra unicolor Moore, 185859`
[WARN] [2020-05-06 10:24:57] Filtered Scientific Name `Miresa nivaha Moore, 1858/59` to `Miresa nivaha Moore, 185859`
[WARN] [2020-05-06 10:24:57] Filtered Scientific Name `Birthama saturata Kiriakoff, 1946/49` to `Birthama saturata Kiriakoff, 194649`
[WARN] [2020-05-06 10:24:57] Filtered Scientific Name `Tetraclonia dyraspes Druce, 1891/901` to `Tetraclonia dyraspes Druce, 1891901`
[WARN] [2020-05-06 10:24:57] Filtered Scientific Name `Clelea pravata Moore, 1858/59` to `Clelea pravata Moore, 185859`
[WARN] [2020-05-06 10:24:57] Filtered Scientific Name `Seryda basirei Druce, 1891/901` to `Seryda basirei Druce, 1891901`
[WARN] [2020-05-06 10:24:57] Filtered Scientific Name `Phauda mahisa Moore, 1858/59` to `Phauda mahisa Moore, 185859`
[WARN] [2020-05-06 10:24:58] Filtered Scientific Name `Trachea macrophtalma Berio, 1976/77` to `Trachea macrophtalma Berio, 197677`
[WARN] [2020-05-06 10:24:58] Filtered Scientific Name `Trachea bipectinata Berio, 1976/77` to `Trachea bipectinata Berio, 197677`