DRUM change forced an update of JIRLbot as no synchronization point is
available anymore. Tests revealed that the synchronized set partly does
not what it states it does, therefore added own implementation
therefore. JUnit-Test for STAR does execute as expected but during
installation surefire fails somehow - have to figure out why surefire
executes unit tests differently than JUnit
REPLACED DRUM constructors with builder pattern as the list of arguments is quite long. MINOR comment and log message improvements
MINOR gitignore update due to switch  from Eclipse to IntelliJ
ADDED base class for cache based unit tests which creates and deletes the base cache directory and initializes a logger. Adapted existing unit test class accordingly.
MINOR logger initialization fix
ADDED super-pom to simplify updating version numbers of dependencies. FIXED broken crawling and added plenty of javadoc and comments. Also applied some code conventions. ADDED look and feel layouts to have visible colors within the crawling GUI
Merge branch 'modifiedDrum'

Conflicts:
	pom.xml
	src/main/java/at/rovo/crawler/RobotsCache.java
	src/main/java/at/rovo/crawler/RobotsRequested.java
	src/main/java/at/rovo/crawler/STAR.java
	src/main/java/at/rovo/crawler/URLseen.java
	src/test/java/at/rovo/test/RobotsCacheTest.java