Add Nokia 6133 (fixes #57)

Signed-off-by: Michal Čihař <michal@cihar.com>
Identify Nokia Asha 306 (closes #20)

Signed-off-by: Michal Čihař <michal@cihar.com>
Add Nokia 112 (fixes #5)

Signed-off-by: Michal Čihař <michal@cihar.com>
A little bit of coding style

Signed-off-by: Michal Čihař <michal@cihar.com>
Complete implementation of UTF-8 encoder

We did miss quite big range of Unicode chars...

Issue #8

Signed-off-by: Michal Čihař <michal@cihar.com>
Simplify unicode encoding functions

Issue #8

Signed-off-by: Michal Čihař <michal@cihar.com>