Rename __add__ method to append for clarity in Cigar class

Author: Donaim

src/aligntools/cigar.py

@@ -410,7 +410,7 @@ def normalize(cigar_lst: Iterable[Tuple[int, CigarActions]]) \
     def __eq__(self, other: object) -> bool:
         return isinstance(other, Cigar) and self._data == other._data
 
-    def __add__(self, other: 'Cigar') -> 'Cigar':
+    def append(self, other: 'Cigar') -> 'Cigar':
         return Cigar(self._data + other._data)
 
     def __repr__(self):

src/aligntools/cigar_hit.py

@@ -208,7 +208,7 @@ def __add__(self, other: 'CigarHit') -> 'CigarHit':
             left = other
             right = self
 
-        combined_cigar = left.cigar + right.cigar
+        combined_cigar = left.cigar.append(right.cigar)
         return CigarHit(cigar=combined_cigar,
                         r_st=left.r_st,
                         r_ei=left.r_st + combined_cigar.ref_length - 1,