Story: Create `Program` struct and implement `serde::Deserialize` for it

[sunkit02]

Epic: #1

Description

Create Program struct and implement serde::Deserialize for it

Tasks

• Task: Handle parsing the "Major in Computer Science" program #7
• Task: Handle "AND" and "OR" operators in course field #8
• Task: Handle "Select x from x" #9
• Task: Handle emphasis and concentrations #10
• Task: Handle Labels #11
• Task: Handle nested "AND" and "OR" operators in course field #16