external aligners complain about changed sequence checksums

[westram]

Reproduce:

• start demo.arb
• call
  • Sequence/Align?/ClustalW fast or
  • Sequence/Align?/mafft
• go
• when reimporting asks, select 'overwrite sequence only'

⇒ warns about sequence checksum change

Warning is caused by aligner changing all 'U' into 'T'

• in case of RNA alignment, revert that change before calculating checksum by [12821]
  • currently done for any alignment
  • [12829] always converts 'T' or 'U' as expected by alignment type, but
    • again reports wanted checksum failures
    • does not convert when aligner input/output are equal, but wrong "T or U" is used throughout one sequence by [12830]
• be more severe on that warning, making clear that the sequence data was modified, not some gaps or sth by [12821]

Related TODOs:

• do not ask whether to overwrite species or sequence when GDE_export is called after aligning by [12818]
• do not wait for key-press if no error?
• auto-format affected alignment by [12813]

[westram]

by [12834]

• do not wait for key-press if no error?

will be (implicitly) implemented by #595

[westram]

Milestone renamed