In Python integers should be compared for equality (`i == j`), not identity (`i is j`). Recent versions of CPython 3.x emit a SyntaxWarning when they encounter this incorrect usage, e.g.
```
$ python3 base58.py
base58.py:110: SyntaxWarning: "is" with a literal. Did you mean "=="?
assert get_bcaddress_version('15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC') is 0
Tests passed
```
Ajust the outputs of gen_base58_test_vectors.py to current test format.
1. Add bech32 vector generation.
2. Add Script-fragments to hexrepr in the format expected by the test.
3. Modify the metadata.
1) Change 'isTestnet' to 'chain' (main/test/regtest)
2) Remove 'addrType'
3) Add 'tryCaseFlip' (True/False on bech32)
Alex Willmer