Add posibility of blocks without brackled and colon in AST Block node.

There were only two type of block with brackles "{}" and with colon ":",
in namespace block may no need any of this. Backward compatibility was
kept.

Signed-off-by: Marek Maksimczyk <marek.maksimczyk@mandos.net.pl>
Bug 427408 - [performance] Create extension point for PHPCompletionProposalCollector

Allow change contexts and resolvers directly from requestor (collector)

Change-Id: Ia576fccf4e529852bb9131e6ef13e5bb502b98ac
Signed-off-by: Dawid Pakuła <zulus@w3des.net>
Bug: https://bugs.eclipse.org/bugs/show_bug.cgi?id=427408
Bug 426384 - Jacoco support
Bug 426384 - Jacoco support (typo)