Added container code placement option (footer or custom)

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803334 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added constants for container code placements

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803336 b8457f37-d9ea-0310-8a92-e5e31aec5664
Renamed GTM event to comply with naming conventions

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803337 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added new text for container code placements

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803338 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated custom code snippet

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803345 b8457f37-d9ea-0310-8a92-e5e31aec5664
Updated custom code snippet

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803348 b8457f37-d9ea-0310-8a92-e5e31aec5664
Added container code placement feature

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@803355 b8457f37-d9ea-0310-8a92-e5e31aec5664
renamed track_downloads function to gtm4wp_track_downloads to prevent any conflict with other plugins/scripts

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@804368 b8457f37-d9ea-0310-8a92-e5e31aec5664
renamed track_downloads function to gtm4wp_track_downloads to prevent any conflict with other plugins/scripts

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@804369 b8457f37-d9ea-0310-8a92-e5e31aec5664
jquery-core dependency for wp_enqueue_script was not working for some sites, changed to simply jquery

git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@804442 b8457f37-d9ea-0310-8a92-e5e31aec5664
additional slash in wp_enqueue_script calls removed


git-svn-id: https://plugins.svn.wordpress.org/duracelltomi-google-tag-manager/trunk@804445 b8457f37-d9ea-0310-8a92-e5e31aec5664