Drop Python 2 support, removed in qBittorrent v4.2.2

I'm qBittorrent developer. https://github.com/qbittorrent/search-plugins/issues/84#issuecomment-619539387

Resolves #67

Dockerfile

@@ -19,7 +19,6 @@ RUN \
  apt-get update && \
  apt-get install -y \
 	gnupg \
-	python \
 	python3 && \
  curl -s https://bintray.com/user/downloadSubjectPublicKey?username=fedarovich | apt-key add - && \
  apt-key adv --keyserver hkp://keyserver.ubuntu.com:11371 --recv-keys 7CA69FC4 && \

Dockerfile.aarch64

@@ -19,7 +19,6 @@ RUN \
  apt-get update && \
  apt-get install -y \
 	gnupg \
-	python \
 	python3 && \
  curl -s https://bintray.com/user/downloadSubjectPublicKey?username=fedarovich | apt-key add - && \
  apt-key adv --keyserver hkp://keyserver.ubuntu.com:11371 --recv-keys 7CA69FC4 && \

Dockerfile.armhf

@@ -19,7 +19,6 @@ RUN \
  apt-get update && \
  apt-get install -y \
 	gnupg \
-	python \
 	python3 && \
  curl -s https://bintray.com/user/downloadSubjectPublicKey?username=fedarovich | apt-key add - && \
  apt-key adv --keyserver hkp://keyserver.ubuntu.com:11371 --recv-keys 7CA69FC4 && \

README.md

@@ -254,6 +254,7 @@ Once registered you can define the dockerfile to use with `-f Dockerfile.aarch64
 
 ## Versions
 
+* **26.05.20:** - Drop Python 2 support, removed in qBittorrent v4.2.2
 * **03.04.20:** - Fix adding search engine plugin
 * **02.08.19:** - Add qbitorrent-cli for processing scripts.
 * **23.03.19:** - Switching to new Base images, shift to arm32v7 tag.