menuconfig: Add show-name mode + small help dialog improvement
menuconfig: Add show-name mode + small help dialog improvement

 - Pressing 'c' ('n' was taken) toggles a mode where the names of all
   symbols are shown before their prompts. This saves going into the
   help display when you just want the name.

 - The name of the symbol/choice now appears in the main text of the
   help dialog rather than in the title, where it might be hard to
   spot, as pointed out by Carles Cufi.

Signed-off-by: Ulf Magnusson <01743f1c1deb1fe75271d62edb65757d98ac0bcb@nordicsemi.no>

finikorg/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,kraj/zephyr,zephyriot/zephyr,ldts/zephyr,zephyriot/zephyr,kraj/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,kraj/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,mbolivar/zephyr,finikorg/zephyr,ldts/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,Vudentz/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,finikorg/zephyr,mbolivar/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,mbolivar/zephyr,ldts/zephyr,kraj/zephyr,explora26/zephyr,nashif/zephyr,nashif/zephyr,explora26/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,explora26/zephyr,zephyriot/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,Vudentz/zephyr,galak/zephyr,zephyriot/zephyr,zephyriot/zephyr,explora26/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,explora26/zephyr,nashif/zephyr,finikorg/zephyr,finikorg/zephyr,kraj/zephyr,punitvara/zephyr