Process all XML namespaces in PubSub ItemProvider

Fixes SMACK-601
Make PacketCollector handle InterruptedException

Fixes SMACK-602
Make XMPPError.Condition.equals null-safe

also make Condition implement CharSequence.

SMACK-603
Smack 4.0.4
Merge branch '4.0'

Conflicts:
	build.gradle
	smack-core/src/main/java/org/jivesoftware/smack/PacketCollector.java
	smack-core/src/main/java/org/jivesoftware/smack/packet/XMPPError.java
	smack-core/src/main/java/org/jivesoftware/smack/util/PacketParserUtils.java
	smack-core/src/main/java/org/jivesoftware/smack/util/StringUtils.java
	smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/provider/ItemProvider.java
Use NO_WRAP/DONT_BREAK_LINES when doing Base64 encoding