Addition of a FAQ (#132)

* Addition of a FAQ

* Add links

Author: Barthelemy

README.md

@@ -34,6 +34,7 @@ This is the repository of the data quality control (QC) software for the ALICE O
       * [Local QCG (QC GUI) setup](doc/Advanced.md#local-qcg-qc-gui-setup)
       * [Information Service](doc/Advanced.md#information-service)
       * [Configuration files details](doc/Advanced.md#configuration-files-details)
+   * [Frequently Asked Questions](doc/FAQ.md)
 <!-- Added by: bvonhall, at:  -->
 
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doc/Advanced.md

@@ -22,7 +22,7 @@
 <!--te-->
 
 
-[← Go back to Modules Development](ModulesDevelopment.md) | [↑ Go to the Table of Content ↑](../README.md) 
+[← Go back to Modules Development](ModulesDevelopment.md) | [↑ Go to the Table of Content ↑](../README.md) | [Continue to Frequently Asked Questions →](FAQ.md)
 
 ## Data Inspector
 
@@ -301,4 +301,4 @@ database connection, the monitoring or the data sampling.
 
 ---
 
-[← Go back to Modules Development](ModulesDevelopment.md) | [↑ Go to the Table of Content ↑](../README.md) 
+[← Go back to Modules Development](ModulesDevelopment.md) | [↑ Go to the Table of Content ↑](../README.md) | [Continue to Frequently Asked Questions →](FAQ.md)

doc/FAQ.md

@@ -0,0 +1,29 @@
+# Frequently asked questions
+
+<!--TOC generated with https://github.com/ekalinin/github-markdown-toc-->
+<!--./gh-md-toc --insert /path/to/README.md-->
+<!--ts-->
+   * [Frequently asked questions](#frequently-asked-questions)
+      * [CCDB repository](#ccdb-repository)
+         * [How to see which objects are stored in the CCDB ?](#how-to-see-which-objects-are-stored-in-the-ccdb-)
+         * [How to delete objects from the CCDB ?](#how-to-delete-objects-from-the-ccdb-)
+
+<!-- Added by: bvonhall, at: 2019-04-10T12:19+0200 -->
+
+<!--te-->
+
+[← Go back to Advanced Topics](Advanced.md) | [↑ Go to the Table of Content ↑](../README.md) 
+
+## CCDB repository
+
+### How to see which objects are stored in the CCDB ?
+
+The easiest is to use the QCG (QC GUI). If you use the central test CCDB, you can use the central test QCG. Simply direct your browser to [https://qcg-test.cern.ch](https://qcg-test.cern.ch).
+
+If for some reason you don't want or can't use the QCG, the CCDB provides a web interface accessible at [http://ccdb-test.cern.ch:8080/browse/](http://ccdb-test.cern.ch:8080/browse/).
+
+### How to delete objects from the CCDB ?
+
+By accessing http://ccdb-test.cern.ch:8080/truncate/path/to/folder you will delete all the objects at the given path. Careful with that please ! Don't delete data of others.<br/>In production it will of course not be possible to do so. 
+
+[← Go back to Advanced Topics](Advanced.md) | [↑ Go to the Table of Content ↑](../README.md)