test: generate random item lengths
src tree: rename utility main code files to main.c
lib: rename LIMIT definitions
mkfs: rewrite to use argp
fuse: rename JGFS2_LIMIT_NAME
test: reorganize code
lib: add msync(2) to dev_unmap_sect
lib: update extent plans
doc/todo: add new notes on memory mappings and crash consistency
doc/todo: update mmap ideas
lib: make library re-usable within a process's lifetime
lib: fix not setting lib_init in jgfs2_{init,new}
lib: don't abort if DEBUG_FATAL not defined
redo: add -DDEBUG_FATAL
lib: allow read-only mappings; improve msync
lib: update fs code for dev mapping changes
lib: update miscellaneous code for mapping changes
lib/tree: accept writable option in node_map