add multi type multiMap (#10) - add multi type **multiMap<T1, T2>** to reduce RAM and speed up lookup. - add multi type **multiMapBS<T1, T2>** binary search version. - add example for multi type - update examples - update readme.md - minor edits
add multi type multiMap (#10) - add multi type **multiMap<T1, T2>** to reduce RAM and speed up lookup. - add multi type **multiMapBS<T1, T2>** binary search version. - add example for multi type - update examples - update readme.md - minor edits