POC for multitenancy

Files added:
1. Rest service- UserManagerService which receives JSON input
2.
SimpleMultiTenantConnectionProvider,WebSessionCurrentTenantIdentifierResolver,LocalSessionFactoryBean
to provide support for multitenancy
3.TestUserManager - To test UserManagerService

DB and Tables to be created in MYSQL as per the below script:
CREATE DATABASE `clinic1`
CHARACTER SET 'latin1'
COLLATE 'latin1_swedish_ci';

CREATE DATABASE `clinic2`
CHARACTER SET 'latin1'
COLLATE 'latin1_swedish_ci';

CREATE TABLE `user` (
`id` INTEGER(11) NOT NULL AUTO_INCREMENT UNIQUE,
`username` VARCHAR(50) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB
CHECKSUM=0
DELAY_KEY_WRITE=0
PACK_KEYS=0
AUTO_INCREMENT=0
AVG_ROW_LENGTH=0
MIN_ROWS=0
MAX_ROWS=0
ROW_FORMAT=DEFAULT;

CREATE TABLE `user` (
`id` INTEGER(11) NOT NULL AUTO_INCREMENT UNIQUE,
`username` VARCHAR(50) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM
CHECKSUM=0
DELAY_KEY_WRITE=0
PACK_KEYS=0
AUTO_INCREMENT=0
AVG_ROW_LENGTH=0
MIN_ROWS=0
MAX_ROWS=0
ROW_FORMAT=DEFAULT;