ENH: Added action normalize that can normalize a FeatureTable[Frequency] with common methods.

[VinzentRisch]

This PR solves #311
This PR depends on qiime2/q2-types#340

• This PR adds a new action that can normalize a FeatureTable[Frequency] with common RNA-seq methods. The action uses the package RNAnorm.
• The action takes as input one FeatureTable[Frequency].
• The gene-lengths input is used to pass the gene lengths and can only be used with the methods TPM and FPKM. It accepts artifacts of type FeatureData[SequenceCharacteristics % Properties("length")].

Run it locally

1. First, clone the repo and checkout the PR branch:

git clone https://github.com/qiime2/q2-feature-table.git
cd q2-feature-table
git fetch origin pull/312/head:pr-312
git checkout pr-312
pip install -e .

Install dependent PR of q2-types

git clone https://github.com/qiime/q2-types.git
cd q2-types
git fetch origin pull/340/head:pr-340
git checkout pr-340
pip install -e .

2. Download test files
   PR-311-feature-table.zip

3. Test it out!
   Run all commands from PR folder

qiime feature-table normalize --i-table feature_table.qza --o-normalized-table norm_tmm.qza --p-method "tmm"  --p-m-trim 0.4 --p-a-trim 0.04
qiime feature-table normalize --i-table feature_table.qza --o-normalized-table norm_ctf.qza --p-method "ctf"  --p-m-trim 0.4 --p-a-trim 0.04
qiime feature-table normalize --i-table feature_table.qza --i-gene-length sequence_characteristics.qza --o-normalized-table norm_fpkm.qza --p-method "fpkm" 
qiime feature-table normalize --i-table feature_table.qza --i-gene-length sequence_characteristics.qza --o-normalized-table norm_tpm.qza --p-method "tpm"
qiime feature-table normalize --i-table feature_table.qza --o-normalized-table norm_uq.qza --p-method "uq" 
qiime feature-table normalize --i-table feature_table.qza --o-normalized-table norm_cuf.qza --p-method "cuf"
qiime feature-table normalize --i-table feature_table.qza --o-normalized-table norm_cpm.qza --p-method "cpm"

[ebolyen]

Let's merge this at the start of the next release cycle.

[ebolyen]

@lizgehret, this is good to go, but do we need to wait for anything in distributions? It's going to add rnanorm as an unpinned dep.

[ebolyen]

@VinzentRisch, could you add a note on this in our changelog under the Dev discussion (it'll be the release preview topic). Thanks!