Allow to start fpfis/httpd-php-dev with xdebug and/or blackfire disabled

Normally, a developer has XDebug disabled during development. They enable the PHP xdebug module only for debug puroposed. However, fpfis/httpd-php-dev starts with xdebug and blackfire PHP modules enabled. Every time when I get up the container, I have to run this command:

$ phpdis xdebug blackfire

But we can add build args that can be set from docker-compose.yml, so that projects can decide to start with xdebug and/or blackfire disabled:

version: '3'
services:
  web:
    build:
      context: .
      args:
        - xdebug_enabled="0"
        - blackfire_enabled="0"
...

Then, in Dockerfile we can default the new arguments to preserve the current behaviour.

As, I've mentioned in #3 (closed), I cannot fork or post a merge request against this project repo, so I'll attach a patch that fixes this issue, here:disable-xdebug-blackfire.patch with this diff:

diff --git a/Dockerfile b/Dockerfile
index 7c79035..10c29b6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -74,6 +74,8 @@ RUN /scripts/install-ci.sh && \
 FROM httpd-php-ci as httpd-php-dev
 ADD supervisor_conf/shell.conf /etc/supervisor/conf.d
 ARG dev_packages="php${php_version}-xdebug"
+ARG xdebug_enabled="1"
+ARG blackfire_enabled="1"
 ADD scripts/install-dev.sh /scripts/
 RUN /scripts/install-dev.sh && \
     phpdismod 95-prod && \
diff --git a/README.md b/README.md
index 5af76e1..bf5e383 100644
--- a/README.md
+++ b/README.md
@@ -62,17 +62,19 @@ docker build --build-arg php_version=5.6 --target httpd-php -t fpfis/httpd-php:5
 The [Dockerfile](Dockerfile) is a multistage file containing multiple targets to build
 
 ## Build arguments
-| arg              | Description                                    | Default  
-|------------------|------------------------------------------------|----------
-|`php_version`     | Version of php to build                        | `5.6`
-|`php_modules`     | List of PHP extensions to install              | `curl soap bz2 calendar exif mysql opcache zip xsl intl mcrypt yaml mbstring ldap sockets iconv gd redis memcached tidy`
-|`oci8_version`    | Version of oci8 library to install (full)      | `2.0.12`
-|`apache2_modules` | List of Apache modules to enable after install | `proxy_fcgi setenvif rewrite`
-|`dev_packages`    | Additional packages to install the dev image   | `gnupg wget curl nano unzip patch git rsync make php${php_version}-xdebug`
-|`composer_version`| Version of Composer to install the dev image   | `1.9.3`
-|`drush_version`   | Version of Drush to install the dev image      | `8.2.3`
-|`USER_ID`         | User ID to use for Apache and PHP              | `1000`
-|`GROUP_ID`        | Group ID to use for Apache and PHP             | `1000`
+| arg               | Description                                    | Default
+|-------------------|------------------------------------------------|----------
+|`php_version`      | Version of php to build                        | `5.6`
+|`php_modules`      | List of PHP extensions to install              | `curl soap bz2 calendar exif mysql opcache zip xsl intl mcrypt yaml mbstring ldap sockets iconv gd redis memcached tidy`
+|`oci8_version`     | Version of oci8 library to install (full)      | `2.0.12`
+|`apache2_modules`  | List of Apache modules to enable after install | `proxy_fcgi setenvif rewrite`
+|`dev_packages`     | Additional packages to install the dev image   | `gnupg wget curl nano unzip patch git rsync make php${php_version}-xdebug`
+|`xdebug_enabled`   | If XDebug is enabled on start                  | `1`
+|`blackfire_enabled`| If Blackfire is enabled on start               | `1`
+|`composer_version` | Version of Composer to install the dev image   | `1.9.3`
+|`drush_version`    | Version of Drush to install the dev image      | `8.2.3`
+|`USER_ID`          | User ID to use for Apache and PHP              | `1000`
+|`GROUP_ID`         | Group ID to use for Apache and PHP             | `1000`
 
 
 ## Contribute
diff --git a/scripts/install-dev.sh b/scripts/install-dev.sh
index 34feaea..8243782 100755
--- a/scripts/install-dev.sh
+++ b/scripts/install-dev.sh
@@ -23,3 +23,13 @@ apt-get clean
 rm -rf /var/lib/apt/lists/*
 rm -rf /tmp/*
 rm -Rf /root/.composer/cache
+
+if [ "${xdebug_enabled}" != "1" ]
+then
+  phpdismod xdebug
+fi
+
+if [ "${blackfire_enabled}" != "1" ]
+then
+  phpdismod blackfire
+fi