Add liblsci to scout.

Does not build at this point. Checkpoint.
Add build of Legion.

TODO: add clean target to clean legion and liblsci.
clean legion
clean everything in liblsci.
lsci-private.h is not used. Remove it.
readme update
start of CGLegionRuntime
work on CGLegionRuntime and rename -legion -> -sclegion
Fix legion flag (now called sclegion).  This causes it to link to -llsci as well.  This doesn't fix problems that came up with compiling programs that use liblsci on mac.  An extra link flag -lstdc++ is needed after the -llsci.  Also, most of the frameworks in the link line need to be removed because they have threading, which causes legion to hang at the end of a program.  May need to run without display capability.
Merge branch 'sclegion' of elmo.lanl.gov:gitlab/scout into sclegion
Checkpoint unimesh progress.
Fix subgrid_bounds_len bug and cache progress.
add some sanity
Merge branch 'sclegion' of elmo.lanl.gov:gitlab/scout into sclegion
Add LegionTaskWrapper Scout pass and some fixes from SC_ to SCOUT_.
Merge branch 'sclegion' of elmo.lanl.gov:gitlab/scout into sclegion
Merge branch 'sclegion' of elmo.lanl.gov:gitlab/scout into sclegion

Conflicts:
	llvm/tools/clang/include/clang/Driver/Options.td
Cache start of rudimentary type system.
Merge branch 'sclegion' of elmo.lanl.gov:gitlab/scout into sclegion
Add more type system things and complete c-unimesh