Joomla Module with Installing Table Not Working - joomla

Question

i am new in joomla development, i am making a form as a module in joomla, i want store data in database with this form, its basically registration type which is totally separate from joomla user. but at installation time this module doesn't create tables in database, i used both methods installing from zip and discover and installed
this is my directory structure
my xml manifest is
<?xml version="1.0" encoding="UTF-8"?>
<extension type="module" client="site" method="install" version="3.0">
<name>Registration Form</name>
<author>Arsalan</author>
<creationDate>9,OCT,2014</creationDate>
<version>1.0.0</version>
<description>This is registration form which will display on homepage </description>
<files>
<filename module="mod_registrationform">mod_registrationform.php</filename>
<filename>mod_registrationform.xml</filename>
<filename>helper.php</filename>
<folder>tmpl</folder>
<folder>sql</folder>
</files>
<install>
<sql>
<file driver="mysql" charset="utf8">sql/install.sql</file>
</sql>
</install>
<update>
<sql>
<file driver="mysql">sql/install.sql</file>
</sql>
</update>
<uninstall>
<sql>
<file driver="mysql" charset="utf8">sql/uninstall.sql</file>
</sql>
</uninstall>
<update>
<schemas>
<schemapath type="mysql">sql/updates</schemapath>
</schemas>
</update>
</extension>
this is sql code which is working fine
CREATE TABLE IF NOT EXISTS `#__helloworld` (
`id` int(10) NOT NULL AUTO_INCREMENT,
`hello` text NOT NULL,
`lang` varchar(25) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=1;
i am tired of searching this problem solution, please help me thanks : )