Merge branch 'feature/gitlab-ci' into 'master'

GitLab CI and sync with GitHub

This change adds GitLab CI support. Currently we pull latest version of esp-idf-template project from Github and try to compile it with esp-idf version in question.
Additional test steps will be added in the future.

This change also adds automatic push to GitHub for master branch only, if CI has passed.

To implement CI builds, I created a docker image, espressif/esp32-ci-env. I will make its Dockerfile available on Github as well.

See merge request !12

.gitlab-ci.yml

@@ -0,0 +1,37 @@
+stages:
+  - build
+#  - test
+  - deploy
+
+
+build_template_app:
+  stage: build
+  image: espressif/esp32-ci-env
+
+  variables:
+    SDK_PATH: "$CI_PROJECT_DIR"
+    IDF_PATH: "$CI_PROJECT_DIR"
+    GIT_STRATEGY: clone
+
+  script:
+    - git clone https://github.com/espressif/esp-idf-template.git
+    - cd esp-idf-template
+    - make all
+
+push_master_to_github:
+  stage: deploy
+  only:
+    - master
+  when: on_success
+  image: espressif/esp32-ci-env
+  variables:
+    GIT_STRATEGY: clone
+  script:
+    - mkdir -p ~/.ssh
+    - chmod 700 ~/.ssh
+    - echo -n $GH_PUSH_KEY >> ~/.ssh/id_rsa_base64
+    - base64 --decode --ignore-garbage ~/.ssh/id_rsa_base64 > ~/.ssh/id_rsa
+    - chmod 600 ~/.ssh/id_rsa
+    - echo -e "Host github.com\n\tStrictHostKeyChecking no\n" >> ~/.ssh/config
+    - git remote add github git@github.com:espressif/esp-idf.git
+    - git push github HEAD:master

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "components/esp32/lib"]
 	path = components/esp32/lib
-	url = ssh://git@github.com:espressif/esp32-wifi-lib.git
+	url = https://github.com/espressif/esp32-wifi-lib.git