Added guide for build deb package on Ubuntu

TheHive4/Installation/Build_sources.md

@@ -29,12 +29,19 @@ npm install -g bower grunt
 cd /opt
 git clone https://github.com/TheHive-Project/TheHive.git
 cd TheHive
-git checkout scalligraph
+git checkout master-th4
 git submodule init
 git submodule update
 ./sbt stage
 ```
-
+To start the backend in dev mode instead 
+```bash
+ ./sbt stage
+ ```
+ do :
+```bash
+./sbt run
+```
 - The UI
 
 ```bash
@@ -43,3 +50,58 @@ npm install
 bower install
 grunt build
 ```
+To start the frontend:
+```bash
+ grunt serve
+```
+
+### Creating deb package on Ubuntu 20.04
+
+```bash
+sudo apt install default-jre 
+sudo apt install apt-transport-https
+sudo apt install fakeroot
+sudo apt install curl
+sudo apt install git
+curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.0/install.sh | bash
+```
+Open a new terminal
+```bash
+nvm install --lts
+npm install -g bower grunt
+```
+```
+git clone https://github.com/TheHive-Project/TheHive.git
+cd TheHive
+git checkout master-th4
+git submodule init
+git submodule update
+```
+```
+./sbt clean debian:packageBin
+```
+After a while you will get something like
+```
+[info] Building debian package with native implementation
+[info] dpkg-deb: building package 'thehive4' in '../thehive4_4.0.2-1_all.deb'.
+[success] Total time: 1032 s (17:12), completed Dec 11, 2020, 10:45:45 AM
+```
+The deb package is located under target folder
+```
+user@user:~/TheHive$ ls -la target
+total 185744
+drwxrwxr-x  8 user user      4096 Dec 11 10:45 .
+drwxrwxr-x 22 user user      4096 Dec 11 10:00 ..
+drwxrwxr-x  2 user user      4096 Dec 11 10:45 global-logging
+drwxrwxr-x  6 user user      4096 Dec 11 10:37 scala-2.12
+drwxrwxr-x  7 user user      4096 Dec 11 10:25 streams
+drwxrwxr-x  2 user user      4096 Dec 11 10:45 task-temp-directory
+drwxrwxr-x  7 user user      4096 Dec 11 10:25 thehive4-4.0.2-1
+-rw-r--r--  1 user user 190167232 Dec 11 10:45 thehive4_4.0.2-1_all.deb
+drwxrwxr-x  4 user user      4096 Dec 11 10:24 universal
+```
+So can install with:
+```
+sudo dpkg -i target/thehive4_4.0.2-1_all.deb
+```
+Ensure to follow the [deb guide](https://github.com/TheHive-Project/TheHiveDocs/blob/master/TheHive4/Installation/Install_deb.md) before install this package.