cleanup iemgui dialog form names, replacing dashes with underscores. Fix stray bugs in canvas dialog, and clean up css selector names

stop using "x" for sending iemgui colors-- while it has a precision formatter, it doesn't have a maximum size formatter (and it can't because 64-bit archs need the larger values)

Death to tcl Part 1 (cont.): remove old uncommented code and sys_vgui calls that are replaced by gui_vmess

update open dialog window height/width/font/fontsize for iemguis as they are resized/repositioned with the mouse

fix iemguis and canvas scalehandle to track mouse position instead of delta-- this fixes a bug when the mouse goes below the minimum dimensions. Plus, some more cleanup of the scalehandle code

further refined legacy mode to match both iemgui and graph-on-parent objects.

second draft of iemgui handles--- still some bugs when switching between canvas gop rect and iemguis

 *added legacy option for iemgui objects. Starting pd-l2ork with -lega…

…cy flag positions iemgui objects in their old, vertically inconsistent locations for the sake of retaining complete backwards compatibility.

*added sys_legacy global for inclusion of other potential legacy breakages that may develop later.

fix "pos" method for [nbx]

change type of scalehandle_new and h_master. Document some structs in g_all_guis.h and change some field sizes.

remove canvas/glist arg in a bunch of recently added iemgui functions, and introduce iemgui_draw_move & iemgui_draw_config

big refactoring #11 : replaced %lxOBJ by x%lx and removed nlet_tag from all iemgui, among other smaller changes

big refactoring #10 : simplifying the _draw_new, _draw_select, _new, _dialog methods, among other things

big refactoring #8 : fusion of [hsl] and [vsl] together, and fusion of [hradio] and [vradio] together

refactor : merge t_iem_fstyle_flags and t_iem_init_symargs into t_iemgui. remove type t_iemguidummy. remove fields x_rcv_able, x_snd_able and x_font. removed redundant arg "void *x" in 9 old g_all_guis.c functions. added dummy "send" method to [vu] for consistency.