Add languages to the database

- Added models for languages and proficiencies
- Added linker model for person, language and proficiency
Add skills to the database

- Refactor the skills models to include a table for proficiency
- Remove relationship table and build new linker table for person, skill
  and proficiency
Add interests to the database
Add awards, publications and cerifications to database
Add reccomendations to the database

- Fix spelling errors
Pass files to be parsed on the command line

- Give either a single file or a directory of files to be parsed
- Refactor reading the files be within ResumeParser()