make all pom.xml/mvn based projects inherit from a generic/shared ALA parent pom.xml

[mbohun]

create:

• [x] ala-parent-pom github repo/project (created by @aruizca )
• [x] add travis-ci.org build for it
• [x] build and deploy the ala-parent-pom into our maven repo, for other pom.xml projects to inherit from

use: for each pom.xml based project inherit from the ala-parent-pom; example from ala-cas/pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

        <parent>
            <groupId>au.org.ala</groupId>
            <artifactId>ala-parent-pom</artifactId>
            <version>1.0</version>
        </parent>

        <modelVersion>4.0.0</modelVersion>
        <groupId>au.org.ala</groupId>
        <artifactId>ala-cas</artifactId>
        <packaging>war</packaging>
        <version>1.0-SNAPSHOT</version>

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