Initial DHT test program.

Support for reading by button clicks added.
Timed readings implemented.

New simple logic for sensor readings through internal timer A0.
Sensor readings fixed.

Some changes from Arduino DHT inserted.
Handshake MCU <-> DHT22 Sensor fixed.
UART -> SPI. More refactorings.

Macros moved to definitions.h, work cycle uses separate files.
Migrating to 16MHz instead 1MHz, UART tested.

Some issues with DHT22, precise constants values should be reviewed.
DHT22 and UART initially works.

Checkpoint revision.
PWM and DHT22 handling updated.

Partial checks has been made.
DHT22 works now.

Small improvements in text formatting.
Constants tuned for reliable measurements.
DHT22 init updated to set line initially HIGH.
Merge branch 'master' of github.com:TheDZhon/hc001