Remove code for detecting FASTA formats and instead rely on the user
providing explicitly the format via a specialized flag.

Add --ncbi-targets, --gencode-targets, --mirbase-targets flags to the
binary.

Use /opt/intel/mkl as a default path for mkl_root.

Each warning that suggest a dependency now also include a corresponding
configuration flag.

We already have explicit flags for enabling MKL LAPACK and FFTW3, so the
warning messages have been removed.

This strategy prevents many useless allocations for lines in-between
sequence records by positioning the stream on the beginning of a new
record.

It also simplifies the parsing code since we don't need to check line[0]
anymore.

The filter relies on hashing MirbookingOccupant structures in order to
determine if an interaction is to be filtered out by the broker.

Move MirbookingOccupant-related routines into mirbooking-occupant.c and
add corresponding declaration in the header file to reuse them in the
binary.

Add an integration test to make sure that the blacklist filtering is
working.

The new GFile-based output format writer does not support opening
/dev/null in replace mode. Moreover, it's useful to view the output
format when testing to assess if the correct output is produced
(requires meson test -v).

Conflicts:
	tests/meson.build