Major refactor of line-line blend calculation into separate source file
Moved more utility functions to blendmath source
Refactored blending completely to abstract main calculations

Blend arc calculations before were a mess of local variables, and most
of the useful calculations were buried in the tpCreateBlendArc function.
This refactor pushes much of the actual math into the blendmath file.
Critically, this change also isolates the blend "parameters" from the
geometry, so that the same blend calculations can be reused for line-arc
blends, multi-axis blends, etc.
Added stretch functions for line and circle
Added trim fields and misc fixes
Refactored TCQ functions into separate source file
Working arc-arc for all cases, needs robustness testing
Added comment updates
Attempt to fix spiral handling in stretch function, reduces overage but not completely
Fix for consumed line length / drift bug
Implemented line-arc and arc0line
Removed old line-arc code
Added ripple control
Added parabolic equivalent sizing to reduce accel ripple
Added canon type fix
Added debug messages and added error conditions for quadratic formula error
Changed restriction on blend radius to convex case only
Overhaul of arc cases to correct majority of errors
Added validation for EmcPose to prevent NaN's from being assigned to trajectory planner output
Implemented temporary "swap" copies of geometry.

By doing re-sizing on a copy, any errors can be easily handled since
there's no roll-back needed.