If e1 Then s1 'Else skip' adaptation

[Pichers]

Description

Simulated an "Else { skip; }" when no else expression is present in the original code.

Related Issue

Closes #11

Type of change

• Bug fix
• New feature
• Documentation update
• Code refactoring

How Has This Been Tested?

Some simple feature tests were ran locally, with no found bugs

[CatarinaGamboa]

Add tests to our testsuit

[CatarinaGamboa]

Are there any news in this PR? @Pichers

[CatarinaGamboa]

Add some more test cases for using values after the if condition like:

this.value = n;
if (x){
    this.value = k;
}
return this.value;

[CatarinaGamboa]

These tests are better but still do not test what I tried to mention last time, see the comments in the PR

[CatarinaGamboa]

Create at least one more separate test where we check if the return type has the permission required after the if conditions.
For the previous example check if the return is still @Unique for example (might need changes):

public @Unique Object test(@Free Object v1, boolean c1){
  Object n;
   n = new Object(); // n is free
  this.value = n; // should be fine
  if (c1){
      this.value = v1; // should be fine
  }
  return this.value; // is this.value still Unique?
}

This way we can check if the information in the context is the expected one.