Description of problem:
In some cases %add_maven_depmap does not include <version> in <maven> part, which causes auto-provides generator to fail.

Either maven_depmap should always include version or auto-provides generator should accept depmaps with missing versions.

Version-Release number of selected component (if applicable):
3.3.0-1

Steps to Reproduce:
1. build junit in rawhide

Actual results:
Traceback (most recent call last):
  File "/usr/lib/rpm/maven.prov", line 74, in <module>
    builder = TagBuilder ()
  File "/usr/lib/rpm/maven.prov", line 46, in __init__
    depmap = Depmap(path)
  File "/usr/lib/python2.7/site-packages/javapackages/depmap.py", line 62, in __init__
    if not self.get_provided_mappings():
  File "/usr/lib/python2.7/site-packages/javapackages/depmap.py", line 107, in get_provided_mappings
    raise DepmapInvalidException("Depmap {path} does not have version in maven provides".format(path=self.__path))
DepmapInvalidException: Depmap /builddir/build/BUILDROOT/junit-4.11-7.fc21.x86_64/usr/share/maven-fragments/junit does not have version in maven provides

Additional info:
Depmap generated by %add_maven_depmap is:

<dependencyMap>
	<dependency>
		<maven>
			<artifactId>junit</artifactId>
			<groupId>junit</groupId>
		</maven>
		<jpp>
			<artifactId>junit</artifactId>
			<groupId>JPP</groupId>
		</jpp>
	</dependency>
</dependencyMap>