Jar loading: Only load jars that match by name, not by prefix

Conflicts:
	sopremo/sopremo-query/src/main/java/eu/stratosphere/sopremo/query/PackageManager.java
Merge branch 'sopremo-jars-by-name' of https://github.com/anjakunkel/stratosphere-sopremo into sopremo-jars-by-name

Conflicts:
	sopremo/sopremo-query/src/main/java/eu/stratosphere/sopremo/query/PackageManager.java