Add seeds

[practicalswift]

Add seeds.

[practicalswift]

Added seeds to new (and some old) harnesses. Now at 7159 added seeds (was 1436).

[practicalswift]

Added seeds. Now at 7929 added seeds (was 7159).

[maflcko]

I plan to hold back on merging this until we decided what to do with std::optional, as that might change the seed format for some fuzzers

[practicalswift]

@MarcoFalke I'm not sure I follow TBH: if we choose to do the std::optional change I'll have to re-create all the existing inputs in the repo for all the affected fuzzers (and also purge no longer needed inputs) regardless of this change, so I don't see how having this PR merged would make the situation worse in that regard? Regardless of what might happen in the future: more coverage now is better than less coverage now, no? :)

[maflcko]

I am not sure what the size limits on GitHub repositories are and I don't want them to shut this repo down. (The repo is append-only and deleting unused seeds is not going to reduce the size of the repo ever again, unless git history is rewritten)

[practicalswift]

@MarcoFalke

FWIW I have hosted a monster size repo with the OS X source for many years at https://github.com/practicalswift/osx without any problems. AFAIK GitHub repos have a size limit of 100 GB, and GitHub handles repos with many millions of files without problems. In the past I've heard that repo search is disabled once you reach 500,000 files in a repo, but everything else continues working as normal.

qa-assets is currently at a very modest 0.7 GB repo size with only 53,825 files, so I think we'll reach the final goal of 100% fuzzing coverage with our inputs long before they fill up these GitHub limits :)