Created a builder class for the Lift class.

[maxrossi91]

I did two major change and one minor changes to help the usability of the library in external projects.

• Created a builder class for the Lift class. (major) The builder class handle the bitverctors that were handled in the LiftMap class. The Lift class can now be also build from the builder class. This allows the decoupling of the construction of the Lift class
• Updated serialize and load for compatibility with sdsl. (major) Now the load and serialize can be used in the same contest as the ones from sdsl.
• Bugfix: The memcpy in the update_cigar function was causing memcpy-param-overlap errors when turning on ASAN. (major). See PR.
• Included an option flag to avoid the definition and the construction of test targets. (minor)