AK2: automatically escape forward slashes (/) for section functions

- use simple replacement to automatically escape forward slashes (/) to make remove_section and replace_section perform like the other functions, since they are needed as part of a sed /pattern/,/pattern/d delete operation
- update documentation

README

@@ -54,8 +54,6 @@ Similarly, "line match string" and "line replace string" are the search strings
 
 You may also use ui_print "<text>" to write messages back to the recovery during the modification process, and contains "<string>" "<substring>" to simplify string testing logic you might want in your script.
 
-Note: the "begin search string" and "end search string" arguments of replace_section and remove_section require any forward slashes (/) to be escaped.
-
 // Instructions
 
 1- Place zImage in the root (dtb should also go here for devices that require a custom one, both will fallback to the original if not included)

anykernel.sh

@@ -116,13 +116,13 @@ replace_string() {
 # replace_section <file> <begin search string> <end search string> <replacement string>
 replace_section() {
   line=`grep -n "$2" $1 | cut -d: -f1`;
-  sed -i "/${2}/,/${3}/d" $1;
+  sed -i "/${2//\//\\/}/,/${3//\//\\/}/d" $1;
   sed -i "${line}s;^;${4}\n;" $1;
 }
 
 # remove_section <file> <begin search string> <end search string>
 remove_section() {
-  sed -i "/${2}/,/${3}/d" $1;
+  sed -i "/${2//\//\\/}/,/${3//\//\\/}/d" $1;
 }
 
 # insert_line <file> <if search string> <before|after> <line match string> <inserted line>