New in version 2.0.
Change underscore-delimited lowercase string to uppercamelcase:
abjad> string = 'bass_figure_alignment_positioning'
abjad> iotools.underscore_delimited_lowercase_to_uppercamelcase(string)
'BassFigureAlignmentPositioning'
Changed in version 2.0: renamed stringtools.underscore_delimited_lowercase_to_uppercamelcase() to iotools.underscore_delimited_lowercase_to_uppercamelcase().