Implemented Docker support

Dockerfile

@@ -0,0 +1,25 @@
+FROM gcc:9.2
+
+ENV DEBIAN_FRONTEND noninteractive
+
+# Installing Dependencies
+RUN apt-get update && apt-get install -y \
+    wget \
+ && rm -rf /var/lib/apt/lists/* 
+
+# Installing CMake
+RUN wget "https://github.com/Kitware/CMake/releases/download/v3.18.3/cmake-3.18.3-Linux-x86_64.sh" \
+ && chmod a+x cmake-3.18.3-Linux-x86_64.sh \
+ && ./cmake-3.18.3-Linux-x86_64.sh --prefix=/usr/local --skip-license \
+ && rm cmake-3.18.3-Linux-x86_64.sh
+
+# Copying files
+COPY . /app
+WORKDIR /app
+
+# Building
+RUN cmake -Hall -Bbuild \
+ && cmake --build build
+
+# Running
+CMD [ "./build/standalone/Greeter" ]