Fix gsettings tool string handling
Fix gsettings tool string handling

There are some bugs caused by the way that gsettings-tool currently
attempts to help the user when they leave the quotes off of a string
value that they are setting.

Simplify the code to make it more robust and add some comments about why
it should be done this way.

https://bugzilla.gnome.org/show_bug.cgi?id=649915

iConsole/Console-OS_external_bluetooth_glib,Distrotech/glib,bluez-android/glib,pstglia/platform-external-bluetooth-glib,zsx/glib,mzabaluev/glib,justinkb/aosp-bluez.glib,ieei/glib,tchakabam/glib,tchakabam/glib,justinkb/aosp-bluez.glib,zsx/glib,iConsole/Console-OS_external_bluetooth_glib,cosimoc/glib,djdeath/glib,01org/android-bluez-glib,krichter722/glib,cosimoc/glib,justinkb/aosp-bluez.glib,lukasz-skalski/glib,MathieuDuponchelle/glib,johne53/MB3Glib,01org/android-bluez-glib,MathieuDuponchelle/glib,darren-clark/android_platform_external_bluetooth_glib,bluez-android/glib,mzabaluev/glib,01org/android-bluez-glib,djdeath/glib,endlessm/glib,ieei/glib,endlessm/glib,ieei/glib,johne53/MB3Glib,pstglia/external-bluetooth-glib,01org/android-bluez-glib,justinkb/aosp-bluez.glib,lukasz-skalski/glib,tamaskenez/glib,justinkb/aosp-bluez.glib,cosimoc/glib,zsx/glib,krichter722/glib,cention-sany/glib,Distrotech/glib,Distrotech/glib,tamaskenez/glib,pstglia/external-bluetooth-glib,gale320/glib,darren-clark/android_platform_external_bluetooth_glib,antono/glib,gale320/glib,pstglia/external-bluetooth-glib,cention-sany/glib,Distrotech/glib,bluez-android/glib,endlessm/glib,iConsole/Console-OS_external_bluetooth_glib,mzabaluev/glib,tamaskenez/glib,djdeath/glib,antono/glib,johne53/MB3Glib,darren-clark/android_platform_external_bluetooth_glib,MathieuDuponchelle/glib,cention-sany/glib,pstglia/external-bluetooth-glib,krichter722/glib,iConsole/Console-OS_external_bluetooth_glib,cosimoc/glib,iConsole/Console-OS_external_bluetooth_glib,tamaskenez/glib,darren-clark/android_platform_external_bluetooth_glib,bluez-android/glib,tchakabam/glib,djdeath/glib,cention-sany/glib,ieei/glib,pstglia/external-bluetooth-glib,djdeath/glib,johne53/MB3Glib,tamaskenez/glib,krichter722/glib,pstglia/platform-external-bluetooth-glib,lukasz-skalski/glib,pstglia/platform-external-bluetooth-glib,cosimoc/glib,antono/glib,endlessm/glib,krichter722/glib,gale320/glib,gale320/glib,cention-sany/glib,MathieuDuponchelle/glib,lukasz-skalski/glib,tchakabam/glib,ieei/glib,darren-clark/android_platform_external_bluetooth_glib,pstglia/platform-external-bluetooth-glib,tchakabam/glib,01org/android-bluez-glib,zsx/glib,lukasz-skalski/glib,antono/glib,gale320/glib,Distrotech/glib,endlessm/glib,mzabaluev/glib,johne53/MB3Glib,mzabaluev/glib,MathieuDuponchelle/glib,johne53/MB3Glib,pstglia/platform-external-bluetooth-glib,bluez-android/glib