Add development dependencies to requirements.txt (#440)

This allows people who use requirements.txt to install dependencies in
their development environment to use sphinx-autobuild.

source/requirements.txt

@@ -3,7 +3,7 @@ babel==2.12.1 ; python_version >= "3.7" and python_version < "4.0"
 beautifulsoup4==4.12.2 ; python_version >= "3.7" and python_version < "4.0"
 certifi==2023.5.7 ; python_version >= "3.7" and python_version < "4.0"
 charset-normalizer==3.1.0 ; python_version >= "3.7" and python_version < "4.0"
-colorama==0.4.6 ; python_version >= "3.7" and python_version < "4.0" and sys_platform == "win32"
+colorama==0.4.6 ; python_version >= "3.7" and python_version < "4.0"
 data==0.4 ; python_version >= "3.7" and python_version < "4.0"
 decorator==5.1.1 ; python_version >= "3.7" and python_version < "4.0"
 doc8==0.11.2 ; python_version >= "3.7" and python_version < "4.0"
@@ -16,6 +16,7 @@ imagesize==1.4.1 ; python_version >= "3.7" and python_version < "4.0"
 importlib-metadata==6.6.0 ; python_version >= "3.7" and python_version < "3.10"
 jinja2==3.1.2 ; python_version >= "3.7" and python_version < "4.0"
 latex==0.7.0 ; python_version >= "3.7" and python_version < "4.0"
+livereload==2.6.3 ; python_version >= "3.7" and python_version < "4.0"
 markupsafe==2.1.2 ; python_version >= "3.7" and python_version < "4.0"
 packaging==23.1 ; python_version >= "3.7" and python_version < "4.0"
 pbr==5.11.1 ; python_version >= "3.7" and python_version < "4.0"
@@ -27,6 +28,7 @@ shutilwhich==1.1.0 ; python_version >= "3.7" and python_version < "4.0"
 six==1.16.0 ; python_version >= "3.7" and python_version < "4.0"
 snowballstemmer==2.2.0 ; python_version >= "3.7" and python_version < "4.0"
 soupsieve==2.4.1 ; python_version >= "3.7" and python_version < "4.0"
+sphinx-autobuild==2021.3.14 ; python_version >= "3.7" and python_version < "4.0"
 sphinx-design==0.1.0 ; python_version >= "3.7" and python_version < "4.0"
 sphinx-hoverxref==1.0.1 ; python_version >= "3.7" and python_version < "4.0"
 sphinx-tabs==3.3.1 ; python_version >= "3.7" and python_version < "4.0"
@@ -42,6 +44,7 @@ sphinxext-opengraph==0.6.3 ; python_version >= "3.7" and python_version < "4.0"
 sphinxext-rediraffe==0.2.7 ; python_version >= "3.7" and python_version < "4.0"
 stevedore==3.5.2 ; python_version >= "3.7" and python_version < "4.0"
 tempdir==0.7.1 ; python_version >= "3.7" and python_version < "4.0"
+tornado==6.2 ; python_version >= "3.7" and python_version < "4.0"
 typing-extensions==4.5.0 ; python_version >= "3.7" and python_version < "3.8"
 urllib3==2.0.2 ; python_version >= "3.7" and python_version < "4.0"
 zipp==3.15.0 ; python_version >= "3.7" and python_version < "3.10"