Work on compilation of [string is].
Hit some problem edge cases with differences in strictness of edge cases that
will force a rethink ([string is boolean] is significantly more strict than
Tcl_GetBooleanFromObj).
merge main dev branch
merge main dev branch
merge dkf-compile-misc-info
merge main dev branch
merge main dev branch
merge main working branch
merge main working branch
redevelop code to have more in common with the interpreted [string is] and to remove non-working types
merge main working branch
merge main working branch
Make DEFAULT_TRIM_SET a MODULE_SCOPE string constant, so its value can be shared in tclCmdMZ.o and TclCompCmdsSZ.o 
and it no longer pollutes the tclStringTrim.h header file.
use compact form
a different approach
extend [string is] to booleans
[2992970] Restore the safety of Tcl_AppendObjToObj(x, x) for bytearrays.
Also moves overflow checking to TclAppendBytesToByteArray() and adds
the ability to call TABTBA() with bytes==NULL, for appending unspecified
bytes.  That is, the string grows, but the new bytes are of undetermined
value.  Like Tcl_NewByteArrayObj(NULL, length) this option is useful
for manipulating buffers.  The TABTBA growth algorithm is also enhanced
a bit, copying over a fuller implementation from GrowStringBuffer()
in tclStringObj.c
added compilation for [nextto]
implementation of [yieldto] in bytecode
[2992970] Restore safety of Tcl_AppendObjToObj(x, x) for bytearrays.
Silence compiler warnings.