README.md, build/make/install: Update - documentation no longer has special log file location

Author: Matthias Koeppe

README.md

@@ -378,7 +378,6 @@ SAGE_ROOT                 Root directory (sage-x.y.z in Sage tarball)
 │       ├── lib/sage      List of installed packages
 │       └── tmp/sage      Temporary files when building Sage
 ├── logs
-│   ├── dochtml.log       Log of the documentation build
 │   ├── install.log       Full install log
 │   └── pkgs              Build logs of individual packages
 │       ├── alabaster-0.7.12.log

build/make/install

@@ -107,7 +107,6 @@ during this run of 'make $@'):
 EOF
 
     look_for_errors "$SAGE_LOGS/*.log" 20 "^Error" package >&2
-    look_for_errors "$SAGE_LOGS/../doc*.log" 100 "^Error" documentation >&2
 
     cat >&2 <<EOF