* tag 'upstream/0.20.0': (664 commits)
libgit2 0.20.0 "anmeldung"
Formatting fix for cred_acquire_cb
util: NetBSD doesn't have qsort_r either
tests: Drop unrelated comment
index: Free the index on git_index_open() failure
tree-cache: Fix error message typo
tree-cache: Don't segfault upon corruption
tree-cache: Zero out the allocated tree children array
tree-cache: Free the tree upon the detection of a corrupted child
cleaning code, removing unused variables
Add content offset to git_diff_line
netops: fix leak
Fix warnings
Introduce git_cred_default for NTLM/SPNEGO auth
Propagate auth error codes as GIT_EUSER in winhttp
Add missing mappings to .mailmap file
Update files that reference tests-clar
Rename tests-clar to tests
Fix warnings
tests: make a few globals statics
...