SamBuilder: add move constructor test

and explicitly default the move constructor
SamBuilder: add constructor test
SamBuilder: make move-assignment default
SamBuilder: add tests to move-assignment
Variant: fix memory leak in generic_string_info_field
SamBuilder: add test for setting empty cigar
SamBuilder: add illegal operator in front of length cigar operator
SamBuilder: more invalid cigars
SamBuilder: add invalid base quality string test
SamBuilder: add explicit initializer_list<uint8_t> set_base_quals test case
Cigar: add copy and move constructor tests
Cigar: add copy assignment test
Cigar: add move assignment test
Cigar: make move constructor and move assignment default
Cigar: add tests for invalid cigar access
Cigar: add test comparing unequal cigars
Cigar: check self assignment in the copy assignment constructor
BaseQual: add copy/move assignment and constructor tests
BaseQuals: make move assignment and constructor default
Cigar: add test for const operator[]
BaseQuals: add test to compare different sized base quals
Cigar: switch boundary checks to utils::check_max_boundary
ReadBases: make move assignment/constructors default
ReadBases: add invalid access tests