Improves usability

[debuti]

• Adds more symbols for 7 segment displays
• Adds setnumber fn to show an integer in a 7s display
• Adds setString to set an string right away

[phd0]

please, correct your code
int trimmed = value % 100000000;
with
unsigned long trimmed = value % 100000000; and so on ...
work better with up 32768 value.