6.3.0

Features:

• Enable single-line annotations with pip-compile --annotation-style=line (#1477). Thanks @AndydeCleyre
• Generate PEP 440 direct reference whenever possible (#1455). Thanks @FlorentJeannot
• PEP 440 Direct Reference support (#1392). Thanks @FlorentJeannot

Bug Fixes:

• Change log level of hash message (#1460). Thanks @plannigan
• Allow passing --no-upgrade option (#1438). Thanks @ssbarnea