Implement reading multiple blocks from SD card (#9)

Add info on image conversion to README.md

Fail faster reading a BMP from SD card

Fail faster reading a BMP from SD card

Optimization ...

- reduce time to read, parse and write a 320x240 BMP from 2.85 to 2.61
  seconds, and there is probably still a lot of potential...

Read BMP images from SD card ...

- improve speed of BMP image parsing (3.4s -> 2.85s)
- some refactoring

Read BMP images from SD card ...

- some cleanup

Update README.md

Read BMP images from SD card (#8) ...

- initialization complete, SD card goes in ready state
- read single block
- write single block 
- some refactoring
- read BMP image raw from SD card starting from given address
- re-enable all glyphs and emojis
- sacrifice two emojis for flash space
- update README

Fix pixel shift of uploaded BMP image

Cosmetics ...

- add braces

Update README.md ...

- mention command to start paint application

Optimization ...

- don't swap endianess once and again, use memcpy

Optimization ...

- use union instead of bitshifts to join bytes

Just some cleanup

Just some cleanup/fix rounding

Initial implementation of touch screen (#7) ...

* Initial implementation of touch screen
* Updated NetBeans configuration
* Read number of touch points, cleanup
* Improve touch support

- avoid duplicate touch events by interrupting on falling edge only
- read touch event flags
- refactoring for better code reuse

* Some more refactoring
* Initial function to draw continuous lines

- connect points with a distance > 1 with linear interpolation during
  touch contact

* Fix conversion from 4-Bit greyscale to 16-Bit RGB

- removes reddish antialiasing that was present with some chars

* Add initial paint toy + related refactoring
* Add some tools with icons
* Add more tools + improvements

- draw rectangles
- set line thickness
- account for line thickness in dimensions

* Update README.md, re-enable all glyphs and emojis.

Simplify, simplify!

Multi display support (#6) ...

- implement hflip + vflip
- reset state when done streaming BMP image
- Makefile settings for 1.8" Color TFT LCD 160x128 ST7735R
- update README.md
- add color inversion for ST7789

Fix shifting (#5) ...

- replace silly assignment with OR + assignment...
- maybe a 4 x 8-Bit buffer + casts is more efficient than a 4 x 32-Bit buffer?

Add snowman emoji

Add snowman emoji

Add snowman emoji (#4)

Smile if emoji is a stranger

Improve scripts

Update README.md

Update README.md

Use font for emojis instead of bitmaps (#3) ...

- add emoji 'font' allowing to enter emojis along with text
- add a tiny Linus bitmap in 4-Bit Grey and 16-Bit RGB

Add emojis 🙂 (#2) ...

- add bitmaps for emojis
- remove large incomplete DejaVu font (just small Hack font for now)
- emojis in 16-Bit RGB

Small improvements ...

- add stty command to cats/cats.sh to set up the terminal
- add/fix comment(s)