Spectrochempy

What's Changed
FIX issue 310
FIX: the order of multicoordinates for a single dimension
FIX: integrate methods to avoid code-climate warnings (duplicate code)
FIX: Documentation for the integrate methods
Documentation improvement
FIX: skipping test_sh under windows
Some code revision
NNMF revision
pip only installation

**NEW FEATURES**

* opus file reader: add filenames as labels.

* Omnic file reader: Documented more .spa header keys.

**BUGS FIXED**

* Compatibility with matplotlib 3.5.

* Datasets were not properly centered in PCA analysis.

* Comparing dataset with only labels coordinates was failing.

* Issue 322 fixed : mean and other API reduce methods were sometimes failing.

New Contributors
* Mailaender made their first contribution in https://github.com/spectrochempy/spectrochempy/pull/319

**NEW FEATURES**

* IRIS: Added 1D datasets.

* IRIS: Added kernel function for diffusion .

* EFA: Added indication of progress.

* Cantera: Added differential evolution algorithm in cantera utilities.

* Cantera: Added PFR object in cantera utilities.

* DOC: Added list of papers citing spectrochempy.

* Github action workflows to test, build and publish conda package and docs in replacement of Travis CI.

* Use CodeClimate to show Coverage info

**BUGS FIXED**

* IRIS example after modification of readers.

* IRIS: automatic search of the L-curve corner.

* MCR-ALS returns the 'soft' concentration matrix.

* Document building configuration after update of external packages.

* DOC: fix several broken links.

* Baseline correction default changed.

* Compatibility with newest change in Colab

Several bugs corrected.

Sample examples now separated in another package/