bugfix: lib/sh/sync.sh: upload(): paths: don't dereference the path itself if it's a symlink; instead canonicalize just its parent dir. this allows syncing a specific file which is a symlink, rather than syncing the symlink's target.

lib/sh/util.sh: added canon_dir_rel_path(), which canonicalizes just the parent dir if the path is a symlink, to leave the symlink itself untouched

planning/workflow/validation/: archived BIEN2 validations documents which have been superseded by planning/goals/BIEN3_derived_data_products.docx, to avoid confusion

planning/workflow/bien3_architecture.pptx: updated with clarifications made in today's conference call

bugfix: bin/map: in_is_db: inline metadata value columns (used by new-style import) so that they can be compared by value in XML simplifying functions (lib/xml_func.py)

lib/sql.py: added col_default_value(), col_is_constant(), which interface with corresponding util-schema functions

lib/sql_gen.py: added col2col_ref() for interfacing with for SQL functions that take a util.col_ref

schemas/util.sql: added is_constant(col_ref), for checking if a column has been marked "constant"

schemas/util.sql: added col_comment()

schemas/util.sql: mk_const_col(): add column comment "constant" to mark column as inlinable (needed by some mappings to have a literal value to compare)