adding CI for docs

.gitignore

 profile.bash
 **.DS_Store
 **/__pycache__
-
 docs/_build/
-docs/book/_build/
\ No newline at end of file

.gitlab-ci.yml

+docs:
+  image: continuumio/miniconda:latest
+  stage: build
+  tags:
+    - docker
+  script:
+    - conda env create --file environment.yml
+    - conda init bash
+    - source ~/.bashrc
+    - conda activate wrfotron_docs
+    - jupyter-book build docs
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