cpsc 490 project

[joshualovejoy]

main changes:

• added a level to dimension/offset table that allows for quick indexing when widths and dimensions are decoupled. also works with staggered encoding optimization.
• updated leaf_to_symbol and update_symbol functions in data_point.h to use dim_off_table
• updated node_path_to_coordinates in tree_block.h to use dim_off_table
• added search_test and insert_test, which verify that insertion, lookup, and range search are still working as intended for various widths