TGM-Plugin-Activation - Multisite Installs can download from WordPress Plugin Directory

 Added additional support for multisite. Allows installation of wordpress plugins from the WordPress Plugin Directory

Made changes because I could not install wordpress plugins from the WordPress Plugin Directory.
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when using wordpress version 3.4.2 with multisite installed
the plugins listed did not correctly point to the WordPress Plugin Directory.


The problem was with the actual location of the plugin-install.php.

single site install of wordpress uses:
wp-admin/plugin-install.php 

multisite uses
wp-admin/network/plugin-install.php 

Added the code
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if ( is_multisite() ) {
     $this->plugin_install_file = admin_url( 'network/plugin-install.php' );}

else{
     $this->plugin_install_file = admin_url( 'plugin-install.php' ); }

-----replaced  code------------------------


replaced:  admin_url( 'plugin-install.php' )
with:      $this->plugin_install_file