Changeset 32

Major change is to implement the new way n-bit data is dealt with, with a new NBITS keyword and changed dimensions in the TDIM string for the data array. Details of changes:

• PSRFits_fileIO.cc -- Add functionality to deal with nbits, as well as generalising the way of determining the size of the data array.
• PSRFits.hh -- added Subint::nbits and accessor functions, as well as functions to get size of data array.
• Header.hh -- add test for file not existing in idSurvey().
• Block.hh -- added new functions Block::saveData() and Block::Header().
• Block.cc -- saveData function, where you can save a data array straight to a Block. Useful for testing functions.
• Utils.hh -- temporary change to getPSRFITSdefn()
• tests/test_s70_data_read.cc -- Test for file not existing.
• tests/test_pttape_read.cc -- Test for file not existing.
• tests/makeFakeData.cc -- Creates fake data files for testing pvoconvert. These have a range of number of bits per datum.
• mainConvert.cc -- Add command-line options to specify whether a given PM/PH file is indeed a PH one.
• Documentation.