Generalize script for extracting sentences

Can extract text using detex now (as an option).

{{cookiecutter.paper_repo_name}}/helpers/get-sentences.sh

@@ -1,3 +1,15 @@
 #!/bin/bash
 
-bash helpers/pdf-to-plain-text.sh "$1" | perl helpers/strip-references.pl | perl -pne 'chomp $_; $_.=" "' | python3 -m syntok.segmenter
+input_file="$1"
+method="$2"
+
+extract_text() {
+    if [[ "$method" == "from-tex" ]]
+    then
+        detex "$input_file" | egrep '\S' | grep -v 'unsrt' | perl -pne 's/^\s+| +$//g'
+    else
+        bash helpers/pdf-to-plain-text.sh "$input_file" | perl helpers/strip-references.pl | perl -pne 'chomp $_; $_.=" "'
+    fi
+}
+
+extract_text | python3 -m syntok.segmenter | egrep '\S'