* Add grandstream_label_background varable
Allows the label background to be toggled
* Add ability to set static ipv4 for gxp2130_40_60_70_35
* Add ability to set static ipv4 for dp750
* Update {$mac}.xml
<P35> expects user_id not display_name
nway_conference == true was evaluating as true regardless if nway_conference was set to true or false, just as long as it had a value of any kind.
This also fixes it so that you can set nway_conference to false in the default settings and it will disable the network conference feature, previously once it was enabled on yealink phones it could not be disabled without manually changing it in the phone or a factory default.
* Add Grandstream Headset/Speaker Ring
Add variable to choose whether the speaker rings with the headset.
* Add Speaker Only option
Add note that speaker only is supported with a value of 2.
Hide the other connected party on the BLF of supported phones. When not hidden a busy BLF will show the other connected party/sttaus of the call by flashing back and forth between the BLF label and the caller ID.
It also impacts the park buttons, but they typically only show the word "park" because of the character limitations.
Also did more effective find/replace for the distnctive ring variables with regex!
Support enabling nway conference with Grandstream phones if nway_conference is set to true. If it is not true, it sets the conference URI back to blank to restore local conference
Grandstream template updates to support plantronics EHS via grandstream_headset_type and grandstream_headset_key_mode variables.
Also updated wallpaper and screensaver if/else statements to leave out the variables if they are not defined instead of clobbering the user setting. If you want to mandate a certain setting, just set the variable. If the variable is unset it will not overwrite on provision and allow the previous setting to remain.
Fix config URL so that the phones don't get an invalid URL when $domain_name is unset. They would previously receive `/app/provision` with no domain/ip included, which makes the phone unable to provision again once they have been added to the Devices page without manually re-setting the config URL or factory defaulting the device.
The alternative solution is that the PHP code could always ensure that the $domain_name variable is set even if the device doesn't exist. My suggestion is to see if it can be set to the same domain/IP as the original provision request from this unconfigured device
