Made it possible to set CC and CXX on commandline before calling script

for those cases when gcc, cc-5.0, icpc or icc isn't in the path.

Fixed handling of 32 and 64 bits.

Downgraded Solaris builds on Forte to use -xO2 rather than -xO3.

Made it possible to build 64-bits on Mac OS X

Fixed some bugs in setting CC, CXX, ASFLAGS, LDFLAGS

Fixed bugs relating to use of SunStudio/Forte in check-cpu

Reorganized code a bit

Removed the use of --with-fast-mutexes since they aren't really
fast, rather slow.

Added -static-libgcc when using gcc

Added optimising compilation flags on BSD

Added use of curses library on Solaris

Removed the use of MY_ATOMIC_MODE_RWLOCKS which removed use of
atomic instructions

Added support for Forte on Solaris/x86

BUILD/check-cpu

@@ -175,6 +175,7 @@ check_cpu () {
     cc=$CC
   fi
 
+  if test "x$compiler" = "x" ; then
     cc_ver=`$cc --version | sed 1q`
     cc_verno=`echo $cc_ver | sed -e 's/^.*(GCC)//g; s/[^0-9. ]//g;	 s/^ *//g; s/ .*//g'`
     set -- `echo $cc_verno | tr '.' ' '`
@@ -214,13 +215,9 @@ check_cpu () {
         return
         ;;
     esac
-
     # now we check whether the compiler really understands the cpu type
     touch __test.c
 
-  if test "x$core2" = "xyes" ; then
-    cpu_arg="core2"
-  fi
     while [ "$cpu_arg" ] ; do
       printf "testing $cpu_arg ... " >&2
            
@@ -236,6 +233,11 @@ check_cpu () {
       break;
     done
     rm __test.*
+  fi
+  if test "x$core2" = "xyes" ; then
+    cpu_arg="core2"
+  fi
+  return 0
 }
  
 check_cpu