Fixed some validation problems with readme.txt

Tested with WordPress readme validator http://wordpress.org/plugins/about/validator/
Fixed some validation problems with readme.txt

Tested with WordPress readme validator http://wordpress.org/plugins/about/validator/
Merge branch 'master' of github.com:laterpay/laterpay-wordpress-plugin
#109 improved sabmenu appearing; updated plugin activation
Merge pull request #128 from laterpay/feature/109_add_submenu_pages

#109 improved sabmenu appearing; updated plugin activation
Fixed paths in plugin-mode-indicator
#48. added check for dit permissiomns
#48. removed unused variable
#48 added a few comments and revised wording if messages
Merge pull request #129 from laterpay/feature/48_requirements_check

#48. added check for write permissions
Fixed broken pointer caused by name changes in menu_pages
Small CSS fix
Updated plugin description in laterpay.php
Merge branch 'refs/heads/master' into feature/121_premium_downloads_shortcode