Minor dependency script updates:

* adding more optional versions to the dependency scripts: RocksDB and syscall_intercept with glibc3 fix as more systems are updated to >glibc3
* Cloning libfabric instead of downloading the tarball. This is because it is configured with a specific autotools version which is not available on all systems. Cloning allows generating `configure` dynamically.
* daemon metadata backend now links to Dynamic Loader which is required by newer systems (not sure when this happened) and newer rocksdb versions
* removing python startup scripts since they are no longer supported and are confusing if part of the git repo

See merge request !57

Resolve "[Testing] test_data fails when statx is not available"

Closes #115

See merge request !54

Resolve "missing fsync"

Closes #110

See merge request !52

Resolve "Add I/O tests"

Closes #107

See merge request !47

Check for statx support

See merge request !49

Resolve "Add lseek tests"

Closes #105

See merge request !45

This fixes #84 by implementing readv and preadv

Closes #84

See merge request !41

Resolve "[Statx] Tests not installed correctly"

Closes #106

See merge request !46

Resolve "statx syscall missing"

Closes #104

See merge request !42

Resolve "Implement a testing harness for functional tests"

Closes #76

See merge request !33