update package subtitle

and remove unnecessary title comment from titlepage.xml

Author: jw-allen

PackageInfo.g

@@ -2,8 +2,7 @@ SetPackageInfo( rec(
 
  PackageName := "SBStrips",
 
- Subtitle := "representing string modules for special biserial algebras, \
-towards syzygy calculations",
+ Subtitle := "for syzygies of string modules over special biserial algebras",
 
  Version := "v0.6.4",
 
@@ -68,7 +67,7 @@ strips. It includes some tests for associated properties such as syzygy type, \
 delooping level and weak periodicity.\n\n SBStrips also includes bookkeeping \
 functionality for multisets, which it calls collected lists, and it \
 integrates with (and depends on) the QPA package for quiver algebras and \
-their modules."
+their modules.",
 
  PackageDoc := rec(
    BookName := "SBStrips",

doc/titlepage.xml

@@ -4,15 +4,14 @@
   &PACKAGENAME;
 </Title>
 
+<Subtitle>
+  for syzygies of string modules over special biserial algebras
+</Subtitle>
+
 <Version>
   Version &VERSION;
 </Version>
 
-<TitleComment>
-  A discrete model of special biserial algebras, string modules and their
-  syzygies
-</TitleComment>
-
 <Author>
   Joe Allen (he/him/his)
 </Author>