Feature: implement splice correction

[philipp-baumann]

• e.g., for ASD sensor data, there are typically sensor gaps at 1000nm and 1800nm. Some of the code can be adapted from simplerspec::correct_join_offset(): https://github.com/philipp-baumann/simplerspec/blob/master/R/read-asd.R .

• enable a column name based or column index based sensor gap specification.