Added the Alps EC11 series dual encoder. (#1)

* Added the Alps EC11 series dual encoder.

Special thanks to Mark_Alpha for creating the 3D model

* Add reference to KLC S2.2 in contributing docs

* added missing footprint filter to the dual encoder

* added keywords

* moved the symbol to center

* thickened outline (kicad symbol rules)

* updated more kicad library rules,
mostly text sizes

* corrected a typo in line wifth that caused weirdness

* added courtyard rectangle

* stroke on silkscreen figures to 0.12mm per guidelines

* fabrication layer figures should be 0.1mm

* Renamed the 3d model of dual encoder to match footprint name EC11EBB24C03

* moved 3d model to 0,0,0

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Co-authored-by: Shane Sewell <[email protected]>