Improved maven project file and updated project README.md to explain how to build and run the compiler.

Author: Bob Garner

README.md

@@ -53,7 +53,20 @@ Although many working microservices have been built using this compiler and its
 
 ## Building and Running
 
-The next release will include a Maven project file that will allow you to build. For now, the current Github release includes a `ec.jar` jar file. To run the compiler simply perform: `java -jar ec.jar` followed by arguments (for instance: `java -jar ec.jar -help`)
+> It is recommended to use version 3.6.0 or above of Maven (use `mvn --version` to get its version if it is already installed).
+
+This repository includes a Maven project file (`pom.xml`). This allows you to build the project and create an "executable" jar file. To do this, open a shell and go inside the repository's local directory (aka Project Directory) and run:
+
+    mvn clean package
+
+This will build the project and produce a directory called `target`. Inside this `target` directory there should be the built jar file `ec.jar`. You may want to move this jar file to a `bin` directory in your local account (such as `~/bin`), then also have a shell script in this `bin` directory that wraps this jar file to appear as a command line executable. For example, you could create a file called just `ec` (located in your `bin` directory) that looks like the following:
+
+```shell
+    #!/bin/sh
+    java -jar ~/bin/ec.jar $@
+```
+
+Then to run the compiler in a shell simply perform: `ec` followed by arguments (for instance: `ec -help`)
 
 ## Licensing
 

pom.xml

@@ -12,7 +12,7 @@
 
     <groupId>org.entityc</groupId>
     <artifactId>Entity-Compiler</artifactId>
-    <version>1.0-SNAPSHOT</version>
+    <version>0.12.1</version>
     <packaging>jar</packaging>
 
     <properties>
@@ -31,16 +31,6 @@
             </plugins>
         </pluginManagement>
         <plugins>
-            <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-jar-plugin</artifactId>
-                <version>3.2.2</version>
-                <configuration>
-                    <archive>
-                        <manifestFile>src/main/resources/META-INF/MANIFEST.MF</manifestFile>
-                    </archive>
-                </configuration>
-            </plugin>
             <plugin>
                 <groupId>org.antlr</groupId>
                 <artifactId>antlr4-maven-plugin</artifactId>
@@ -62,6 +52,7 @@
             </plugin>
             <plugin>
                 <artifactId>maven-assembly-plugin</artifactId>
+                <version>3.3.0</version>
                 <executions>
                     <execution>
                         <phase>package</phase>
@@ -71,6 +62,7 @@
                     </execution>
                 </executions>
                 <configuration>
+                    <finalName>ec</finalName>
                     <appendAssemblyId>false</appendAssemblyId>
                     <archive>
                         <manifest>
@@ -131,4 +123,4 @@
             <version>4.9</version>
         </dependency>
     </dependencies>
-</project>
+</project>