ELFs are now loaded as MemoryRegions so they don't need special handling
anywhere. This also allows file backed COW optimizations to work. This
was not the case before.
This patch removes now obsolete LoadableELF and unused ELF files from
LibElf.
I was loading program headers of both executable and interpreter but
that is incorrect. The interpreter will itself load the program headers
of the executable.
Bananymous