QuaC - First major review

QuaC pipeline has been modified to make it user-friendly and share interface similar to other pipelines at CGDS.

Note that one major deviation compared to our other pipeline is that QuaC uses recent snakemake version (6.0.5), and they are made available via conda environment. That is, we don't use snakemake module from cheaha.

The following may need review at some level. Note: This list is not exhaustive.

• Snakemake pipeline
• Documentation. I kept it simple; let me know if it needs more info.

CONTRIBUTING.md

+# Contributing
+
+## How to contribute?
+
+Follow the [CGDS' best practices for code development](http://cgds.uab.edu/manual-of-operations/standards-definitions/#standard-practices) (see sections IDE, Source Control, Peer Reviews). The [Repo owner](./README.md#Repo-owner) is responsible for reviewing, keeping standards, and accepting the merge request into `origin/master`. Below is the brief listing of this process:
+
+- Create new Git branch based off of the relevant branch (`origin/master`).
+- Make your changes/additions within the new branch.
+- Push branch to GitLab and submit the completed changes/additions via a GitLab merge request. In the merge request form, choose `MERGE REQUEST TEMAPLTE` in the drop-down for `Title` and then complete merge request form in `Description` section with appropriate details.
+- [Repo owner](./README.md#repo-owners) will review the request and provide feedback, if any.
+- When deemed complete, repo owner will merge this branch to master.
+
+
+## Cloning the repository/pipeline
+
+See [README.md](./README.md#installation). If you are cloning branch other than `master`, use `-b` option to specify the branch.