[PATCH] Set the GID in the .env file

[pranavannam at gmail.com]

From: Pranav Annam <pranavannam at gmail.com>

When we create the .env file  the UID is set, but we also need to set the GID,that
can be done by explicitly setting it in the .env file.
If the GID is not set when we go for the next step i.e the 'docker-compose build'
it fails the docker build with: 'You must define GID in .env'
Although the error message is self explanatory it is good to update documentation
to reduce the burden on the developer to run into
this build failure first.

Signed-off-by: Pranav Annam <pranavannam at gmail.com>
---
 docs/development/installation.rst | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/docs/development/installation.rst b/docs/development/installation.rst
index 03ad67a..6a50b74 100644
--- a/docs/development/installation.rst
+++ b/docs/development/installation.rst
@@ -30,6 +30,9 @@ configure Patchwork using Docker:
    .. code-block:: shell
 
       $ echo "UID=$UID" > .env
+      
+#. The above command will create a environment file (.env) which is by default a hidden file with content 'UID=1000' (the UID value is differnt for different machines).Now open the file and set the GID same as the UID and save the file.
+     
 
 #. Build the images. This will download over 200MB from the internet:
 
-- 
2.17.1