H2Store tries to create tables multiple times

AAA H2Store code surrounding table creation is not synchronized, resulting in dangerous race conditions. Below is one such example of this:

2015-12-15 04:50:42,923 | INFO | qtp2032590313-78 | DomainStore | 235 - org.opendaylight.aaa.h2-store - 0.3.0.SNAPSHOT | in dbConnect, domains Table does not exist, creating table
2015-12-15 04:50:42,923 | INFO | config-pusher | DomainStore | 235 - org.opendaylight.aaa.h2-store - 0.3.0.SNAPSHOT | in dbConnect, domains Table does not exist, creating table
2015-12-15 04:50:42,947 | ERROR | config-pusher | StoreException | 235 - org.opendaylight.aaa.h2-store - 0.3.0.SNAPSHOT | Cannot connect to database server org.h2.jdbc.JdbcSQLException: Table "DOMAINS" already exists; SQL statement:
CREATE TABLE DOMAINS (domainid VARCHAR(128) PRIMARY KEY,name VARCHAR(128) UNIQUE NOT NULL, description VARCHAR(128) , enabled INTEGER NOT NULL) [42101-185]