Add required Python packages

On some systems pip and setuptools are no longer installed as
dependencies of the python packages. This commit adds the requirement
for these packages.

docs/en/get-started-cmake/linux-setup-scratch.rst

@@ -17,7 +17,7 @@ To compile with ESP-IDF you need to get the following packages:
 
 - Ubuntu and Debian::
 
-    sudo apt-get install git wget libncurses-dev flex bison gperf python python-serial cmake ninja-build ccache
+    sudo apt-get install git wget libncurses-dev flex bison gperf python python-pip python-setuptools python-serial cmake ninja-build ccache
 
 - Arch::
 

docs/en/get-started-cmake/linux-setup.rst

@@ -15,7 +15,7 @@ To compile with ESP-IDF you need to get the following packages:
 
 - Ubuntu and Debian::
 
-    sudo apt-get install git wget libncurses-dev flex bison gperf python python-serial cmake ninja-build ccache
+    sudo apt-get install git wget libncurses-dev flex bison gperf python python-pip python-setuptools python-serial cmake ninja-build ccache
 
 - Arch::
 

docs/en/get-started/linux-setup-scratch.rst

@@ -12,7 +12,7 @@ To compile with ESP-IDF you need to get the following packages:
 
 - Ubuntu and Debian::
 
-    sudo apt-get install git wget make libncurses-dev flex bison gperf python python-serial
+    sudo apt-get install git wget make libncurses-dev flex bison gperf python python-pip python-setuptools python-serial
 
 - Arch::
 

docs/en/get-started/linux-setup.rst

@@ -14,7 +14,7 @@ To compile with ESP-IDF you need to get the following packages:
 
 - Ubuntu and Debian::
 
-    sudo apt-get install gcc git wget make libncurses-dev flex bison gperf python python-serial
+    sudo apt-get install gcc git wget make libncurses-dev flex bison gperf python python-pip python-setuptools python-serial
 
 - Arch::
 

docs/zh_CN/get-started/linux-setup-scratch.rst

@@ -12,7 +12,7 @@
 
 - Ubuntu 和 Debian::
 
-    sudo apt-get install git wget make libncurses-dev flex bison gperf python python-serial
+    sudo apt-get install git wget make libncurses-dev flex bison gperf python python-pip python-setuptools python-serial
 
 - Arch::
 

docs/zh_CN/get-started/linux-setup.rst

@@ -16,7 +16,7 @@ Linux 平台工具链的标准设置
 
 - Ubuntu and Debian::
 
-    sudo apt-get install gcc git wget make libncurses-dev flex bison gperf python python-serial
+    sudo apt-get install gcc git wget make libncurses-dev flex bison gperf python python-pip python-setuptools python-serial
 
 - Arch::
 

requirements.txt

@@ -1,5 +1,9 @@
 # This is a list of python packages needed for ESP-IDF. This file is used with pip.
 # Please see the Get Started section of the ESP-IDF Programming Guide for further information.
 #
+setuptools
+# The setuptools package is required to install source distributions and on some systems is not installed by default.
+# Please keep it as the first item of this list.
+#
 pyserial>=3.0
 future>=0.16.0