Resolve "Add fragment size distribution"

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PR checklist

• This comment contains a description of changes (with reason)
• If you've fixed a bug or added code that should be tested, add tests!
• Documentation in docs is updated
• CHANGELOG.md is updated
• README.md is updated

Closes #27 (closed)

docs/index.md

@@ -87,6 +87,9 @@ experimentQC | *.FRiPscore.tsv | File containing FRiP score
 experimentQC | *.TSSenrichment.tsv | File containing TSS enrichment
 experimentQC | *_large_tss-enrich.pdf | TSS Enrichment heatmap and metagene plot
 experimentQC | *_tss-enrich.pdf | TSS Enrichment metagene plot
+experimentQC | *.fragment_length_linear.pdf | Paired-end only, fragment/insert size densities, linear
+experimentQC | *.fragment_length_linear.pdf | Paired-end only, log10 fragment/insert size densities
+experimentQC | *.fragment_length_count.txt | Paired-end only, count and fragment length, raw data
 multiqcReport | multiqc_report.html | Quality control report of percent mitochondria, NRF, PBC1, PBC2, NSC, and RSC. Also contains software versions and references to cite.
 
 
@@ -96,7 +99,7 @@ multiqcReport | multiqc_report.html | Quality control report of percent mitochon
     2. crossReads/*cc.plot.pdf: make sure your sample data has the correct signal intensity and location.  See [HERE](https://ccg.epfl.ch//var/sib_april15/cases/landt12/strand_correlation.html) for more details.
     3. filterReads/sample/*.pbc.qc: column 6 (NRF) > 0.9, column 7 (PBC1) > 0.9, and column 8 (PBC2) >3.
     4. experimentQC/coverage.pdf, experimentQC/heatmeap_SpearmanCorr.pdf, experimentQC/heatmeap_PearsonCorr.pdf: See [HERE](https://deeptools.readthedocs.io/en/develop/content/list_of_tools.html) for more details.
-    5. experimentQC/: Common Quality controls for ATAC-seq: FRiP score and TSS enrichment
+    5. experimentQC/: Common Quality controls for ATAC-seq: FRiP score, TSS enrichment, Fragment/Insert length densities (paired-end only)
 
 
 ## Common Errors