Fix 2777 - Add IBM openapi validator

doc/ale-openapi.txt

@@ -0,0 +1,42 @@
+===============================================================================
+ALE OpenApi Integration                                     *ale-openapi-options*
+
+===============================================================================
+ibm-validator                                        *ale-openapi-ibm-validator*
+
+Website: https://github.com/IBM/openapi-validator
+
+
+Installation
+-------------------------------------------------------------------------------
+
+Install ibm-openapi-validator either globally or locally: >
+
+  npm install ibm-openapi-validator -g  # global
+  npm install ibm-openapi-validator     # local
+<
+Recommended plugin for openapi filetype detection:
+
+  https://github.com/hsanson/vim-openapi
+
+Options
+-------------------------------------------------------------------------------
+
+g:ale_openapi_ibm_validator_executable   *g:ale_openapi_ibm_validator_executable*
+                                         *b:ale_openapi_ibm_validator_executable*
+  Type: |String|
+  Default: `'lint-openapi'`
+
+  This variable can be set to change the path to lint-openapi.
+
+
+g:ale_openapi_ibm_validator_options       *g:ale_openapi_ibm_validator_options*
+                                          *b:ale_openapi_ibm_validator_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be set to pass additional options to lint-openapi.
+
+
+===============================================================================
+  vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl: