NanoSim v3.0.0 pre-release

Here we are announcing NanoSim v3.0.0 pre-release, and we will make it an official one once the manuscript is published. Please note that the tar ball attached doesn't contain any pre-trained models, so the downloading will be much faster.

In this release, NanoSim is able to simulate metagenomes with variable abundance profiles.

Key features include:

1. Quantify species abundance level, which is not readily available in existing abundance quantification tools

2. Simulate multiple samples in one batch

3. Simulate chimeric reads in metagenome mode and genome mode

4. Simulate abundance variance deviated from expected value

Bug fixes and small improvements:

1. Fixed the bug in fastq simulation which leads to discrepancy between quality score length and sequence length

2. Changed the way of importing model files, allowing better compatibility

3. Re-trained all the models to be compatible with the model importing

4. Added 2 more pre-trained models for metagenome datasets