Fold antelope/flex and asHost into libCom

Build lexer and parser from libCom/Makefile.
Since libCom now includes asLib.c and asLib_lex.c we must build
antelope and flex without linking them to Com.  This works because
they only need epicsTempFile anyway.  However make doesn't like a
subdirectory with the same name as a target object, so the antelope
source directory is now called yacc.  The two main.c files were also
renamed to avoid other build problems.

Merge asHost into Com and remove mentions in CONFIG_BASE

Lots of noise since SRCS must be renamed to Com_SRCS

src/libCom/gpHash/Makefile

@@ -9,5 +9,5 @@
 
 SRC_DIRS += $(LIBCOM)/gpHash
 INC += gpHash.h
-SRCS += gpHashLib.c
+Com_SRCS += gpHashLib.c
 HTMLS += gpHash/gpHash.html