Fix copy constructor of default implementation of bit vector
Create default implementation of ranked bit vector.

This class has 'rank' implemented (method 'countBits').
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Refactored count array
Refactor count array
Merge branch 'implementation-of-rank-and-select' of https://github.com/Wikidata/Wikidata-Toolkit.git into implementation-of-rank-and-select
Implement method to find the position of a value in ranked bit vector
Simplify the method to update the counts
Improve memory use of the array to find the position of a bit value
Split the implementation of ranked bit vector into smaller classes
Use observer pattern
Add toString method to auxiliary types of ranked bit vector
Extend test class to test findPosition method
Improve javadoc
Make minor improvements in javadoc
Rename auxiliary class
Make algorithm a little clearer
Apply changes according to code review
Apply minor changes in javadoc
Remove convenience constructor in auxiliary classes