Eeschema: non-autoplaced fields feature

Currently, autoplacing fields is the default and affects all shown fields in a symbol.

If a field/property is used as an indicator (+, -, •), it should not be rearranged when a symbol is rotated or mirrored.

Normal text would not be affected, but a user couldn't change/move/hide it in the schematic. So it would be nice to have e.g. a lock attribute for a property, or if their name starts with ki_indicator*, .etc., so that they would be excluded from (but not ignored by) autoplacing.

It could also help to keep the value in the center of European style (international) resistor symbols.

Example symbols: see C (+), L (•), R (+ is invisible but useful for simulations)

KiCad Version

Application: KiCad

Version: (5.99.0-3379-gdb40e0c595), release build

Libraries:
	wxWidgets 3.0.5

Platform: Windows 8 (build 9200), 64-bit edition, 64 bit, Little endian, wxMSW

	wxWidgets: 3.0.5 (wchar_t,wx containers,compatible with 2.8)
	Boost: 1.73.0
	OCE: 6.9.1
	Curl: 7.71.0
	ngspice: 32
	Compiler: GCC 10.2.0 with C++ ABI 1014

Build settings:
	KICAD_SCRIPTING=ON
	KICAD_SCRIPTING_MODULES=ON
	KICAD_SCRIPTING_PYTHON3=OFF
	KICAD_SCRIPTING_WXPYTHON=ON
	KICAD_SCRIPTING_WXPYTHON_PHOENIX=OFF
	KICAD_SCRIPTING_ACTION_MENU=ON
	BUILD_GITHUB_PLUGIN=ON
	KICAD_USE_OCE=ON
	KICAD_SPICE=ON