update PageSnapshot, replace functions

C. Fahner <info@fahnerit.com>
update PageSnapshot system,
allow for PageSnapshot instance retrieval from database
then modify it locally
and store the modified version as the new PageSnapshot

C. Fahner <info@fahnerit.com>
remove default NULL value for textIds to prevent accidental removes

C. Fahner <info@fahnerit.com>
add getter for textIds by language (fahnerit_web/PageSnapshot)

C. Fahner <info@fahnerit.com>
add getBestFitLayoutId to fahnerit_web/PageSnapshot class

C. Fahner <info@fahnerit.com>
add format PageSnapshot function

C. Fahner <info@fahnerit.com>
add ApiCall fahnerit_web/page_snapshot for loading snapshots

C. Fahner <info@fahnerit.com>