Expression Oversimplification

[rcosta358]

Closes #163 and #164. Expressions were simplified to the fullest (e.g., true), which was not helpful to see in the error message, especially in the terminal version which does not allow for expansion.

To fix this, two changes were made:

• Added a condition to stop and use the unsimplified expression If an expression is simplified to a boolean literal
• Added unwrapDerivedLiterals that is called after the simplification is performed, to traverse the derivation tree and replace boolean literals with the expressions that produced them, but only when at least one operand in the derivation is non-boolean (otherwise the boolean literal is okay)

Examples

Before & After

x > 5 && x == 10 → 10 > 5 → true
x > 5 && x == 10 → 10 > 5

Before & After

x == y > 0 && y == 1 → x == 1 > 0 → x == true
x == y > 0 && y == 1 → x == 1 > 0

Before & After

... → 1 == 1 && 2 == 2 → true && true → true
... → 1 == 1 && 2 == 2

[CatarinaGamboa]

lgtm