It can be helpful to verify that the 'struct commit_graph' that results
from parsing a commit-graph is correctly structured. The existence of
different chunks is not enough to verify that all of the optional
features are correctly enabled.
Update 'test-tool read-graph' to output an "options:" line that includes
information for different parts of the struct commit_graph.
In particular, this change demonstrates that the read_generation_data
option is never being enabled, which will be fixed in a later change.
Signed-off-by: Derrick Stolee <derrickstolee@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>