Rationalise ./configure
- borrow a lot of ideas from Michael ABBOTT ( http://sourceware.org/ml/crossgcc/2008-12/msg00030.html )
- should be conforming to POSIX 1003.1-2008, non compliance due to bashsims is to be considered a bug
- as a result, it now works with dash
- make a little easier to read in some places
- enforce 4-space indentation
- get rid of futile 'return $?'
- quote all variables assignments
- save and restore IFS prior to and after using alternate values
- simplify the TOOLS_TO_CHECK listing

What's left:
- provide a mean to actually _compare_ version numbers
- change the TOOLS_TO_CHECK pattern style to be able to use '|' in regexp

/trunk/configure | 243 127 116 0 ++++++++++++++++++++++++++++++++------------------------------
1 file changed, 127 insertions(+), 116 deletions(-)

 # ltrace

 config DEBUG_ltrace

     select TOOL_libelf

     help

       ltrace is a program that simply runs the specified command until it exits.

       It intercepts and records the dynamic library calls which are called by

       the executed process and the signals which are received by that process.

       It can also intercept and print the system calls executed by the program.

 choice

     bool

     prompt "ltrace version"

 config LTRACE_V_0_4

     bool

     prompt "0.4"

 config LTRACE_V_0_5

     bool

     prompt "0.5"

 # CT_INSERT_VERSION_ABOVE

 # Don't remove above line!

 endchoice

 config LTRACE_VERSION

     string

     default "0.4" if LTRACE_V_0_4

     default "0.5" if LTRACE_V_0_5

 # CT_INSERT_VERSION_STRING_ABOVE

 # # Don't remove above line!