Turned external dependencies error into a warning dialog box, enabled individual compile errors again. Added EXE output list.

Fixes for new compiling attempt, also fixed "compile" errors due to external dependencies in ResegFromTree.

Locked add mitosis code which tries to minimally change tree structure on adding a mitosis to a locked tree.

Fix to make sure mitosis edges are always part of valid split list. Also added specific error for relink tracks being empty.

This is because the submarine detection code runs Michel, which can take a
while.  Upstream code can call this function multiple times with different
alphas, but we only want to call the slow Michel code once.

A better solution would probably be to refactor things to make the calling code
smarter, but at least this makes things better for the time being.

Fixes to try and avoid any empty or non-logical entries in otherwise boolean structure fields. This has a really big performance impact on large structure field concatenations.