* device/include/pic16/pic18fregs.h: added case for pic18f2220.h

* device/include/pic16/pic18fregs.h: added case for pic18f2220.h
* device/include/pic16/pic18f2220.h: NEW,
* device/lib/pic16/libdev/pic18f2220.c: NEW,
* device/lib/pic16/libdev/Makefile: added 18f2220 in DEVS,
* src/pic16/device.c (struct Pics16): added info for 18f2220,
* src/pic16/device.h (struct pic16_options): added ivt_loc and
nodefaultlibs, ivt_loc is the location of the interrupt vector
table, and nodefaultlibs signs that default libraries should not be
linked in link stage,
* src/pic16/gen.c (genFunction): relocate interrupt vector functions
according to --ivt-loc argument,
* src/pic16/main.c (_process_pragma): emit '_stack' as public symbol
when pragma stack is found,

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@3368 4a8a32a2-be11-0410-ad9d-d568d2c75423