Sum-It: fix build

There's no package with cmd:rez available. Build and use the one
in Sum-It's source.
Also improve description, summary and copyright.

Strangely, even though the source code hasn't changed since revision 3,
Sum-It now doesn't crash anymore when pasting from clipboard...

haiku-apps/sum_it/sum_it-0.2beta.recipe

@@ -1,14 +1,12 @@
-SUMMARY="Sum-It is a native spreadsheet"
-DESCRIPTION="
-Sum-It is a spreadsheet for BeOS (Download BeOS for free). This is Open \
-Sum-It, the open source version of Maarten Hekkelman's Sum-It application. \
-Sum-It has many features, including a plug-in architecture for formulas and \
-graphs. This product includes software developed by Hekkelman Programmatuur B.V."
+SUMMARY="A native spreadsheet application"
+DESCRIPTION="This is the open source version of Maarten Hekkelman's Sum-It \
+application. Sum-It has basic features, including a plug-in architecture for \
+formulas and graphs and im/export of comma or tab separated files."
 HOMEPAGE="https://github.com/HaikuArchives/OpenSumIt"
-COPYRIGHT="1996-1998, 2000	Hekkelman Programmatuur B.V.  All rights reserved.
-	1999-2000 Tim Vernum. All rights reserved."
+COPYRIGHT="1996-1998, 2000 Hekkelman Programmatuur B.V.
+	1999-2000 Tim Vernum"
 LICENSE="BSD (4-clause)"
-REVISION="4"
+REVISION="5"
 SOURCE_URI="https://github.com/HaikuArchives/OpenSumIt/archive/cdab184a27.tar.gz"
 CHECKSUM_SHA256="064cd9eeab62b0bab12400d23d922b912c46baccd9040dd04e8b16afd91bf70a"
 SOURCE_DIR="OpenSumIt-cdab184a27cb9bbf0f088384a9ecfb07b9daefdc"
@@ -31,7 +29,6 @@ BUILD_PREREQUIRES="
 	cmd:gcc
 	cmd:flex
 	cmd:bison
-	cmd:rez
 	"
 
 BUILD()
@@ -41,6 +38,10 @@ BUILD()
 	PATH=`pwd`:$PATH
 	popd
 
+	pushd rez
+	BE_C_COMPILER=gcc make DEBUG=0
+	PATH=`pwd`:$PATH
+	popd
 
 	cd sum-it
 	BE_C_COMPILER=gcc make DEBUG=0