build: add dash minimal development environment container

Co-authored-by: UdjinM6 <UdjinM6@users.noreply.github.com>

.dockerignore

@@ -1,3 +1,4 @@
 **
 !contrib/containers/ci/Dockerfile
 !contrib/containers/deploy/Dockerfile
+!contrib/containers/develop/Dockerfile

contrib/containers/ci/Dockerfile

@@ -69,6 +69,7 @@ RUN mkdir /dash-src && \
   chown $USER_ID:$GROUP_ID /dash-src && \
   chown $USER_ID:$GROUP_ID /cache && \
   chown $USER_ID:$GROUP_ID /cache -R
+
 WORKDIR /dash-src
 
 USER dash

contrib/containers/develop/Dockerfile

@@ -0,0 +1,32 @@
+# syntax = edrevo/dockerfile-plus
+
+FROM ubuntu:focal
+
+INCLUDE+ ci/Dockerfile
+
+# The inherited Dockerfile switches to non-privileged context and we've
+# just started configuring this image, give us root access
+USER root
+
+# Discourage root access, this is an interactive instance
+#
+# Sometimes these commands are run repetitively _after_ the non-sudo
+# user was introduced and therefore these commands would fail
+# To mitigate the build halting, we've added "|| true" so that it
+# unconditionally returns 0
+#
+RUN apt-get update && apt-get install $APT_ARGS sudo && rm -rf /var/lib/apt/lists/*
+RUN usermod -aG sudo dash
+RUN echo '%sudo ALL=(ALL) NOPASSWD:ALL' >> /etc/sudoers
+
+# Make development environment more standalone
+RUN apt-get update && apt-get install $APT_ARGS nano openssh-client zsh gdb && rm -rf /var/lib/apt/lists/*
+
+# Disable noninteractive mode
+ENV DEBIAN_FRONTEND="dialog"
+
+# Expose Dash P2P and RPC ports for main network and test networks
+EXPOSE 9998 9999 19998 19999
+
+# We're done, switch back to non-privileged user
+USER dash

contrib/containers/develop/docker-compose.yml

@@ -0,0 +1,29 @@
+version: "3.9"
+services:
+  container:
+    entrypoint: /bin/bash
+    build:
+      context: '..'
+      dockerfile: './develop/Dockerfile'
+    tty: true         # Equivalent to -t
+    stdin_open: true  # Equivalent to -i
+    ports:
+      - "9998:9998"           # Mainnet Ports
+      - "9999:9999"
+      - "19998:19998"         # Testnet Ports
+      - "19999:19999"
+
+# A note about volumes:
+#
+# If Docker is interacting with your operating system directly
+# without an intermediate VM, then you do not need to change anything
+#
+# But if not, then you'll need to mount your system's root directory
+# (i.e. /) into the boot2docker instance if you want to mirror the exact
+# filesystem structure of your host.
+#
+    volumes:
+      - type: bind
+#        source: /host/$PWD # Workaround needed on non-Linux hosts
+        source: ../../..
+        target: /dash-src