[pom_editor] minor code cleanup
[pom_editor] Workaround missing attrname in old version of lxml
[pom_editor] Workaround Element.find behaving differently in old lxml
[xmvn-builddep] Use python3, if needed
[build] We want to know what went wrong...
[pom_editor] Improve compatibility with lxml 3.3 and python 3

This fixes "AttributeError: attribute 'attrname' of 'lxml.etree._ElementUnicodeResult' objects is not writable"
[test] python 2.6 zipfile.is_zipfile() says "False" for empty zip files, add something into them...
[test] Enable all tests
[mvn_artifact] Append dependencies to metadata, if we have them
[mvn_artifact] Skip optional dependencies
Revert "[mvn_artifact] Skip optional dependencies"

This reverts commit 32fcc8f3525707c5f68821fc4b8a38e13960c586.

We have to generate R on optional dependencies, because there is a bug in Maven:
http://jira.codehaus.org/browse/MNG-5056
http://jira.codehaus.org/browse/MNG-5145
Remove eclipse project files: .project and .pydevproject

We don't need these in SCM.
[metadata] Read OSGi Requires from manifest only if osgi.id property is missing in metadata

Missing osgi.requires key in properties doesn't mean that we should
always try to read Requires from manifest manually. XMvn skips this
property, if there are no interesting Requires.
[java-utils] Properly escape flags and options

Also fix some possible quotation problems

Resolves: rhbz#1132224