Improved documentation both visually and content-wise
Changed NLargestVisitor to take N as constructor parameter instead of template parameter (backward incompatible change)
Implemented get_top_n_[data|view]()
Implemented get_bottom_n_[data|view]()
Implemented get_above_quantile_[data|view]()
Implemented get_below_quantile_[data|view]()
Added period parameter to ReturnVisitor visitor
Implemented starts_with()
Implemented ends_with()
Implemented CumCountVisitor visitor
Implemented in_between()
Implemented peaks()
Implemented valleys()
Made reading/writing large files faster
Implemented apply()
Made replace() faster with better algorithm
Implemented truncate()
Implemented a version of load_column() with functor generating data
Implemented explode()
Implemented reading/writing std::pair columns from/to files
Added more sanity checks
Implemented difference()
Implemented get_[data|view]_at_times()
Implemented get_[data|view]_before_times()
Implemented get_[data|view]_after_times()
Implemented get_[data|view]_on_days()
Implemented get_[data|view]_in_months()
Implemented get_[data|view]_on_days_in_month()
Implemented get_[data|view]_between_times()
Implemented remove_top_n_data()
Implemented remove_bottom_n_data()
Implemented remove_above_quantile_data()
Implemented remove_below_quantile_data()
Implemented remove_data_by_stdev()
Implemented get_[data|view]_by_stdev()