Update installing on Linux

Change `apt-get` to `apt`.
Minor language fixes.

Author: fdmarcin

book/01-introduction/sections/installing.asc

@@ -14,22 +14,22 @@ Since Git is quite excellent at preserving backwards compatibility, any version
 ==== Installing on Linux
 
 (((Linux, installing)))
-If you want to install the basic Git tools on Linux via a binary installer, you can generally do so through the basic package-management tool that comes with your distribution.
-If you're on Fedora for example (or any closely-related RPM-based distro such as RHEL or CentOS), you can use `dnf`:
+If you want to install the basic Git tools on Linux via a binary installer, you can generally do so through the package management tool that comes with your distribution.
+If you're on Fedora (or any closely-related RPM-based distribution, such as RHEL or CentOS), you can use `dnf`:
 
 [source,console]
 ----
 $ sudo dnf install git-all
 ----
 
-If you're on a Debian-based distribution like Ubuntu, try `apt-get`:
+If you're on a Debian-based distribution, such as Ubuntu, try `apt`:
 
 [source,console]
 ----
-$ sudo apt-get install git-all
+$ sudo apt install git-all
 ----
 
-For more options, there are instructions for installing on several different Unix flavors on the Git website, at http://git-scm.com/download/linux[].
+For more options, there are instructions for installing on several different Unix distributions on the Git website, at http://git-scm.com/download/linux[].
 
 ==== Installing on Mac