pfx_tree: Destroy should work for null tree's
pfx_tree: Finish allocation code for new child nodes
main: Add option parsing and help code
main: Remove other subst options as they are bash specific
pfx_tree: Init should fail when allocation fails
pfx_tree: Prefix check should be done on the children instead of parents
pfx_tree: Memmove size should be in bytes, not units of struct pfx_tree_node
pfx_tree: The key should be assigned for new child nodes
main: Check substitution inserts to make sure they succeed
pfx_tree: Add test suite
main: Refactor out test driven functionality
pfx_tree_test: Refactor some test functionality into a common core
util_tests: Add initial boilerplate
util_test: Implement utf8 test cases
pfx_tree_test: Fix test case for safe inserts
pfx_tree: Correct the behavior of safe insert for longer prefixes
test/common: Allow for test fixtures
tests/util: Add tests for the substitute_file function
pfx_tree: Add height function
src/util: Substitute file correctly reads and writes without substitution