cmDspCtx.h, cmDspNet.h/c, cmDspSys.c, Makefile.am: Added cmDspStore.

Added kReturnUnknownLexFl configuration flag.  If this flag is set
tokens which are not recognized will be returned with the
token id set to kUnknownLexTId.  This is useful for returning all text.

Added kUserDefPriorityLexFl configuration flag.  User defined tokens
take priority even if an identifier (kIdentLexTId) has a longer match.

Added cmLexEnableToken().  This function allows tokens recognizers to be
enabled and disabled.

Parameter type flags (cmBoolPoFl, ...) are now private.
Added 'Flag' parameter type.
Added Enum master help string.
Improved built-in help text content and formatting.
cmHexPoFl is now a parameter configuration flag rather than a type.

Added kRecurseLInksFsFl and kLinkFsFl.
Changed stat() to lstat() in _cmFileSysIsLink().
Added _cmFileSysIsSocket()

This change is goes with cmGrFltk.cpp calls to cmGrDevCtxResize() which
now set the location as well as the size of the device context.

Added state[] variable to XFader DSP object.
Completed _cmDspSysPgm_AvailCh() example program.

Rewrote cmGr.c::cmGrEvent()
Callback cmGrIsInsideObj() now must evaluate both if the mouse point is
inside the object and also if the object can handle the event. This
allows the actual plot object which can handle an event to be identified
by cmGrEvent().

_cmGrPlotObjEvent() still needs to be updated to account for these changes.