Revise hard-coded download schedules

We should tweak the download schedules in config.c based on what we've learned in legacy/trac#20499 (moved).

These schedules should retry sooner than never: TestingServerDownloadSchedule TestingClientDownloadSchedule

These schedules retry at most every 2 hours, should that be higher? TestingServerConsensusDownloadSchedule

These schedules retry at most every 12 hours, should that be higher? lower? TestingClientConsensusDownloadSchedule

These schedules retry at most every 73 hours, should that be lower? Should we try more times before jumping to retrying after an hour? ClientBootstrapConsensusAuthorityDownloadSchedule ClientBootstrapConsensusFallbackDownloadSchedule ClientBootstrapConsensusAuthorityOnlyDownloadSchedule

Should we try more than 7 or 8 times to get directory documents? TestingConsensusMaxDownloadTries ClientBootstrapConsensusMaxDownloadTries TestingDescriptorMaxDownloadTries TestingMicrodescMaxDownloadTries TestingCertMaxDownloadTries