[+] Execute pip packages installation in a separate shell, fixes #3

Author: pashagolub

src/install-packages.bat

@@ -0,0 +1,11 @@
+@ECHO off
+
+SET PIP=pip3.exe
+
+@ECHO --- Installing Patroni packages ---
+CD patroni
+%PIP% install --no-index --find-links .patroni-packages -r requirements.txt
+%PIP% install --no-index --find-links .patroni-packages psycopg2-binary
+@ECHO --- Patroni packages installed ---
+
+@ECHO --- You may close this terminal window ---

src/install.bat

@@ -1,17 +1,13 @@
 @ECHO off
 
 SET PYTHON=python.exe
-SET PIP=pip3.exe
+
 
 @ECHO --- Installing Python runtime ---
 python-install.exe /quiet InstallAllUsers=1 PrependPath=1 Include_test=0 Include_launcher=0
+%PYTHON% -m pip install --upgrade pip
 @ECHO --- Python runtime installed ---
 
-@ECHO --- Installing Patroni packages ---
-%PYTHON% -m pip install --upgrade pip
-CD patroni
-%PIP% install --no-index --find-links .patroni-packages -r requirements.txt
-%PIP% install --no-index --find-links .patroni-packages psycopg2-binary
-@ECHO --- Patroni packages installed ---
+START cmd.exe /k install-packages.bat
 
 @PAUSE