Add "/" to 'phone' keyboard as a new key shown at long pressing zero

[dmitriy-chernysh]

Fix #239 App version 5.4.8

Changes:

• Added a new key "/" right after the dot for 'phone' keyboard.
• Added a way to define the popup key width on the fly [MyKeyboardView.class line 1011]. The existing implementation didn't allow to add more than 4 popup keys to a numeric keyboard cause of width is equal to the main key width.
• Tested all other keyboard types to make sure it works as before.

Before:

After

[dmitriy-chernysh]

@tibbi Fixed

[tibbi]

thanks, looks good now

[sudoshindo]

@tibbi sellout