+ added
  - vesper can run as debugger to write branch information to database
  - vesper can run as analyzer to analyze branch information and symbol information from database

+ changed
  - `BranchLogger::initialize()` method has db_path parameger
  - size field added to `MODULE_TABLE` 
  - Debugger class has changed due to `db_path`, `module_size parameger`.
  - unit test has changed due to `db_path`, `module_size parameger`.

+ doing
  - implementing symbol information for loaded modules