Building from source updates - Maven

Here's a commit that should solve our problems/concerns.

I was able to reproduce the same problems you were having with the Javadoc warnings. These warnings just indicate Javadoc syntax errors throughout the liferay-portal project. These don't have anything to do with Maven. However, just like you experienced, it took an extremely long time to install the artifacts (on 6.1). When I tried installing the artifacts 
for 6.2, I ran into Java heap space problems due to the large amount of Javadoc/warnings. Therefore, I added a warning section to alert readers of potential problems and how to deal with them.

The other big thing I did was what you also eluded to before. Steps 7 and 8 are not necessary because those ant targets are automatically invoked in the install and deploy ant calls. So I removed those. Besides those kinks, it ran smoothly for me. Thanks!