Improve requirements page in documentation

doc/index.markdown

@@ -87,7 +87,7 @@ Technical details
 
 ### Installation
 
-- [Recommended configuration](recommended-configuration.markdown)
+- [Requirements](requirements.markdown)
 - [Installation instructions](installation.markdown)
 - [Upgrade Kanboard to a new version](update.markdown)
 - [Installation on Ubuntu](ubuntu-installation.markdown)

doc/installation.markdown

@@ -1,13 +1,7 @@
 Installation
 ============
 
-Requirements
+Firstly, check the [requirements](requirements.markdown) before to go further.
-------------
-
-- Apache or Nginx
-- PHP >= 5.3.3 (Kanboard is compatible with PHP 5.3, 5.4, 5.5, 5.6 and 7.0)
-- PHP extensions required: mbstring, gd and pdo_sqlite
-- A modern web browser
 
 From the archive (stable version)
 ---------------------------------

doc/recommended-configuration.markdown

@@ -1,36 +0,0 @@
-Recommended Configuration
-=========================
-
-Server side
------------
-
-- Modern Linux/Unix operating systems: **Ubuntu/Debian or FreeBSD**
-- The most recent version of PHP and Apache (Kanboard is compatible with PHP 5.3, 5.4, 5.5, 5.6 and 7.0)
-- Use Sqlite database only when you have a disk with fast I/O (SSD disks) otherwise use Mysql or Postgresql
-
-Client side
------------
-
-- Use a modern browser: **Mozilla Firefox or Google Chrome or Safari**
-
-Tested configurations
----------------------
-
-The following configurations are tested with Kanboard but that doesn't mean all features are available:
-
-### Server
-
-- Ubuntu 14.04 LTS
-- Debian 6, 7 and 8
-- Centos 6.x and 7.0
-- Windows 2012 Server
-- Windows 2008 Server
-
-### Desktops
-
-- Last version of Mozilla Firefox, Safari and Google Chrome
-- Microsoft Internet Explorer 11
-
-### Tablets
-
-- iPad mini 3

doc/requirements.markdown

@@ -0,0 +1,101 @@
+Requirements
+============
+
+Server side
+-----------
+
+### Compatible Operating Systems
+
+| Operating System               |
+|--------------------------------|
+| Linux Ubuntu Trusty 14.04 LTS  |
+| Linux Centos 6.x               |
+| Linux Centos 7.x               |
+| Linux Redhat 6.x               |
+| Linux Redhat 7.x               |
+| Linux Debian 8                 |
+| FreeBSD 10.x                   |
+| Microsoft Windows 2012 R2      |
+| Microsoft Windows 2008         |
+
+### Compatible Databases
+
+| Database           |
+|--------------------|
+| Sqlite 3.x         |
+| Mysql >= 5.5       |
+| MariaDB >= 10      |
+| Postgresql >= 9.3  |
+
+Which database to choose?
+
+| Type            | Usage                                               |
+|-----------------|-----------------------------------------------------|
+| Sqlite          | Single user or small team (almost no concurrency)   |
+| Mysql/Postgres  | Larger team, high-availability configuration        |
+
+Do not use Sqlite on NFS mounts, use Sqlite only when you have a disk with fast I/O
+
+### Compatible Web Servers
+
+| Web Server         |
+|--------------------|
+| Apache HTTP Server |
+| Nginx              |
+| Microsoft IIS      |
+
+Kanboard is pre-configured to work with Apache (URL rewriting).
+
+### PHP Versions
+
+| PHP Version    |
+|----------------|
+| PHP >= 5.3.3   |
+| PHP 5.4        |
+| PHP 5.5        |
+| PHP 5.6        |
+| PHP 7.x        |
+
+### PHP Extensions Required
+
+| PHP Extensions required    | Note                          |
+|----------------------------|-------------------------------|
+| pdo_sqlite                 | Only if you use Sqlite        |
+| pdo_mysql                  | Only if you use Mysql/MariaDB |
+| pdo_pgsql                  | Only if you use Postgres      |
+| gd                         |                               |
+| mbstring                   |                               |
+| openssl                    |                               |
+| json                       |                               |
+| hash                       |                               |
+| ldap                       | Only for LDAP authentication  |
+| Zend OPcache               | Recommended                   |
+
+### Recommendations
+
+- Modern Linux or Unix operating system.
+- Best performances are obtained with the latest version of PHP with OPcode caching activated.
+
+Client side
+-----------
+
+### Browsers
+
+Always use a modern browser with the latest version if possible:
+
+| Browser                               |
+|---------------------------------------|
+| Safari                                |
+| Google Chrome                         |
+| Mozilla Firefox                       |
+| Microsoft Internet Explorer >= 11     |
+| Microsoft Edge                        |
+
+### Devices
+
+| Device            | Screen resolution  |
+|-------------------|--------------------|
+| Laptop or desktop | >= 1366 x 768      |
+| Tablet            | >= 1024 x 768      |
+
+Kanboard is not yet optimized for smartphones. It's working but the user interface is not really convenient to use.

doc/windows-apache-installation.markdown

@@ -65,7 +65,6 @@ extension_dir = "C:/php/ext"
 Uncomment these PHP modules:
 
 ```ini
-extension=php_curl.dll
 extension=php_gd2.dll
 extension=php_ldap.dll
 extension=php_mbstring.dll

doc/windows-iis-installation.markdown

@@ -15,7 +15,6 @@ PHP installation
 Edit the `php.ini`, uncomment these PHP modules:
 
 ```ini
-extension=php_curl.dll
 extension=php_gd2.dll
 extension=php_ldap.dll
 extension=php_mbstring.dll