docker improvement - create pre-QtHost image (or QtSRC)

The image should come bundled with the following: 

• CMAKE
• Python (3.10)
• CONAN
• Git
• Vim
• Bash
• Curl
• Unzip
• Qt build dependencies
• Clone Qt SRC
• Create the USER + Add USER to SUDO

Make the docker image ready for Qt compilation. 

End result, for Qt host:

FROM QtSRC
RUN CONFIGURE_QT
RUN BUILD_QT <at specific path>
RUN SET_BUILD_SUMMARY
ENV EXPOSE_VARIABLES

End result, for Qt+Wasm or Qt+Android

FROM QtHost
RUN INSTALL_SDK <wasm or android>
RUN CONFIGURE_QT
RUN BUILD_QT <at specific path>
RUN SET_BUILD_SUMMARY
ENV EXPOSE_VARIABLES

Paths for Qt: 

• /opt/qt-v<version>/src
• /opt/qt-v<version>/host
• /opt/qt-v<version>/wasm
• /opt/qt-v<version>/android-<abi>
• /home/qt-user/<android-sdk>
• /home/qt-user/<emsdk>
• /home/qt-user/bin <- path for various binary files or scripts