1.10.1 - Fixed fast line drawing in GFXcanvas* classes

Bump to 1.10.1

Grayscale OLED support

Mono OLED removed, replaced with generic grayscale support, tested with 1-bpp and 4-bpp

1.9.0 - Add access to pixel values in GFXCanvas* classes

Thanks to @michaelkamprath for the contribution 👍

1.8.5 - Changed `boolean` to `bool` to avoid compiler warnings

Bump to 1.8.5

1.8.4 - Added missing header to fontconvert.c

Bump to 1.8.4

1.8.3 - Update MonoOLED i2c constructor to match variable definition order

Update version in library.properties to 1.8.3

Some small fix PR's merged

thanks to @rafw87 for #282

and @CombiesGit for #275

Remove Attiny from Mono OLED compilation

it won't fit anyways, so we don't compile it for attiny85

Mono OLED helper subclass & minifixes

Added monochrome oled helper that does dirty rectangle tracking, and many common monochrome display thingies. Could be used with other mono displays i'm sure

Some bug fixes & cleanups thanks to @ZinggJM + @BillyDonahue

Fix for Software SPI on 8-bit processors

Merge pull request #272 from makermelissa/master

Removed duplicate spiWrite to fix bbSPI