Code optimization

Merge as much as possible stuff from second loop to first. Use second
only to set width and X for ports.

More folding
Clean some magic height changes. Bottom space now consists of
max(port_spacing, port_spacingT) + border width - trailing port_spacing.
Port types are traversed in loop, using array.

First stage of refactoring.
Fixed indentation of line, added in visual correction of lineHinting
effect.

Use single rect through all drawing sequence (change of decrement in one
place affects all next steps).

By shifting border inside of logical bound, free space around is
increased by one line weight.

Other related bits

Fixes text for plugin knobs being clipped in some desktop environments.

Do not happen in our code, I think, but a good practice anyway

It expects fast response from backend, which is not what happens
with plugins (using pipes).
For now, just force the change manually
Fixes #671

It expects fast response from backend, which is not what happens
with plugins (using pipes).
For now, just force the change manually
Fixes #671