Let doxygen recurse into subdirs
Further block documentation
Only attempt a single read in spy_at()
Add a first index to each block
Silence signed/unsigned comparison warnings
Add iterator TODO
Rename m_size to m_last

This better reflects its meaning.
Begin work on shrinking blocks in delete_min

Blocks are not merged yet, therefore we run into errors in the block
allocator.
Shrink/merge in clsm::delete_min
A new random ins/del testcase
Add debug print functions