- nvgTextBreakLines: wordMinX was relative to rowStartX, which caused
problems when rowStartX change on line break, but wordMinX was still
relative to the previous rowStartX
- fixed font size on perf graphs
- made demo to use row minx/maxx instead of row->width
- fixed demo hover distance

This commit fixes the demo’s font sizes for the changes in #558, which makes the rendered font size matches what you saw on other native apps. The demo used bigger font sizes than they actually were. This commit deduces the font sizes to match the original demo’s look.

This commit fixes the issue caused by #357 that nanovg failed to compile on iOS due to the wrong way of including glext header.

This commit fixes the formats as suggested in #299 and fixes stack overflow when using `freetype` backend.

- nvglImageHandle was changes to contain GL postfix, changed GL utils
to use that too
- fixed silly failure check bug in FBO demo

The `NVGLUframebuffer` structure contains a `ctx` member but was actually never used. This commit takes advantage of the `ctx` property so there is no need to keep the reference of the context elsewhere after calling `nvgluCreateFramebuffer()`, or it would add difficulty for maintenance. As a result, the `nvgluDeleteFramebuffer()` function only needs to take one `NVGLUframebuffer` instance as the parameter.

- API changed!
- moved image repeat from nvgImagePattern() into image creation
nvgCreateImage*()
- made flip-y and premultiplied common image flags (not just GL)
- removed nvglImageFlags(), flags passed in via
nvglCreateImageFromHandle() flags
- nvgluCreateFramebuffer takes image flags as param

- added NVG_DEBUG which can be used to omit calls to glGetError()
- removed return value for glnvg__checkError
- create flag defines to enum

- added function to allow to combine scissor rects using intersection

- added typedefs for all structs
- fixed some compiler warnings

Tweaked premake to remove some windows warnings.

- all colors in the shader is handled as premultiplied
- removed alphaBlend param from nvgBeginFrame(), it became obsolete
- added NVGL_TEXTURE_PREMULTIPLIED flag
- separated FBO example
- FBOs are treated as premultipied for correct alpha
- changed FBO storage from depth/stencil 24/8 to stencil 8
- moved discard to end of shader which restores the render speed again

- added (optional) 3-pass stencil trick to stroke rendering, reduces
overdraw artifacts, a little slower
- fixed some text bounds issues

- Added alpha for images
- Added global alpha

- fixed flags setup in nvglCreateImageFromHandle
- changed frame buffer to only compile on GL3
- changed nvgluCreateFramebuffer() to return FBO struct instead of
filling existing one (for consistency)

- fixed copy/paste bug in bevel calculations

- line caps did not consider AA width

GLFW_NO_GLU is a GLFW 2 feature.  GLFW 3 does not include the GLU header
by default.

- added documentation about changed GL state
- made old GL2 and GL3 backends obsolete

- added test for multiple stroke widths
- allow stroke width down to 1px size, then scale with alpha
- fixed textBoxBounds() in hi-dpi

- nvgTextBounds() API changed, assumes x,y as input too
- fixed nvgTextBounds() return values
- added nvgTextBoxBounds()
- text line width is handle more consistently
- added note about return values of text measure funds
- changed demo to show text(box)bounds usage

- made uniform buffer support behind separate define for easier toggling
- calculate scissor and stroke alpha outside type selection to simplify
the shader (or else it produces rendering artefacts)
- restore default pixel store settings instead of restoring old state
- set active texture to 0 when starting to render a frame

- added support for GL(ES)2 for nanovg_gl3buf (something is still not
quite there)
- nanovg now sets all required GL state
- removed compiler warnings about unused vars

- calculate all text related stuff using scaling
- removed a couple of compiler warnings
- tweaked caret picking

- fixed some warnings
- changed nvgLetterSpacing() to nvgTextLetterSpacing()
- added nvgTextBox()
- added nvgTextLineHeight()
- added some documentation

- added debug configs for the lib
- added more data for font stash text iterator (ptr to current and next
position in string, code point)
- renamed nvgVertMetrics() to nvgTextMetrics()
- added nvgTextGlyphPositions() which returns glyph x position for the
text
- added nvgTextBreakLines breaks a text into multiple rows based on
newlines and max row width
- tweaked tessellation tolerance

Currently working with gl3buf backend.

- added support to take screen shots
- added support to render to frame buffer using premultiplied alpha
- fixed spelling NVGaling -> NVGalign

- Renamed FPScounter to PerfGraph
- dump avg times at exit

- moved performance counter and drawing to separate file
- tweaks to performance drawing