Missing pattern functions

[mikowitz]

Mesh

• get_path
• get_control_point
• get_corner_color
• begin_patch / end_patch / patch_count (this ends up being the same as defining multiple meshes and setting them as source)

Solid (new type)

• from_rgb (new in Elixir most likely), same as set a solid color and paint).

SurfacePattern (new type)

Sets a surface as the pattern from which color/alpha data is drawn

Linear

• linear_points
• color_stop_count,
• color_stop_rgba

Radial

• get_radial_circles
• color_stop_count
• color_stop_rgba

Shared

• status
• extend, set_extend
• filter, set_filter
• matrix, set_matrix
• get_type
• user_data? (what exactly is this?)

[mikowitz]

Addressed in #55
Addressed in #57

[mikowitz]

Linear gradients addressed in #59

[mikowitz]

Radial gradients addressed in #60

[mikowitz]

Solid pattern addressed in #61

[mikowitz]

Surface pattern addressed in #62