Add a stop_after_block_import field to the BlockManager options. Use
this field instead of the global gArgs.
This should allow users of the BlockManager to not rely on the global
Args.
Add a blocks_dir field to the BlockManager options. Move functions
relying on the global gArgs to get the blocks_dir into the BlockManager
class.
This should eventually allow users of the BlockManager to not rely on
the global Args and instead pass in their own options.
Remove access to the global gArgs for the fastprune argument and
replace it by adding a field to the existing BlockManager Options
struct.
When running `clang-tidy-diff` on this commit, there is a diagnostic
error: `unknown type name 'uint64_t' [clang-diagnostic-error] uint64_t
prune_target{0};`, which is fixed by including cstdint.
This should eventually allow users of the BlockManager to not rely on
the global gArgs and instead pass in their own options.
