Merge pull request #1115 from sashadt/o15demo

O15demo
Enrichment operator for 015 demo.
Support specification of keys to be added to input tuple on match.
Handle exception correctly.
Fix WAL recovery

use readFully instead of read to read byte array from WAL, as sometimes
read only reads partital data from stream, causing futher reads to get
corrupted data.
Merge pull request #1120 from tushargosavi/walfix

Fix WAL recovery
Merge pull request #1117 from tushargosavi/o15demo

Enrichment operator for 015 demo.
Adding default fileStore.basePath location of DefaultDimensionStore
Adding support for string in query keys