splint fix for GT_LU and GT_LD formatcodes
Merge pull request #94 from ggonnella/formatcodefix

splint fix for GT_LU and GT_LD formatcodes
remove some very old files which seem unnecessary
remove separate skproto binary

skproto is not used in gt anyway and we still keep it as dev tool for now
remove unused splint target (spgt is used)

rename SPsplintoptions to Splintoptions
name the files for gt_repfind() consistently
remove the dependency on ncurses

I don't know anyone who has used this experimental feature over the years.
But the external dependency on ncurses caused a lot of pain for users and
developers, therefore I removed it completely.
That is, the previous behaviour with curses=no is now the default.
update zlib to 1.2.8
Merge pull request #95 from gordon/master

add 64bit=yes to Windows 64-bit build script
Merge pull request #98 from gordon/deprecated

remove some very old files which seem unnecessary
Merge pull request #99 from gordon/skproto

remove separate skproto binary
Merge pull request #100 from gordon/splint

remove unused splint target (spgt is used)
Merge pull request #103 from gordon/zlib

 update zlib to 1.2.8
define range macros for GtUword and GtWord
Merge pull request #105 from ggonnella/rangemacros

define range macros for GtUword and GtWord
dist target cannot depend on manuals anymore

for cross-compiles we have to build the manuals before
cosmetics
fix `make manuals`
allow to override strip command

for cross-compilation
add build script for different Linux ARM targets