add a script to check for some basic translation syntax errors

tools/check-translations.sh

@@ -0,0 +1,7 @@
+echo potential errors, if any:
+
+# a space after the percent sign 
+# results in an IllegalFormatException in getString()
+grep --include='strings.xml' -r '\% '
+grep --include='strings.xml' -r '\$ '
+grep --include='strings.xml' -r ' \$'

tools/tx-pull-source.sh

@@ -1,3 +1,4 @@
 tx pull -l en
 mv res/values-en/strings.xml res/values/strings.xml
 rmdir res/values-en
+./tools/check-translations.sh

tools/tx-pull-translations.sh

@@ -0,0 +1,2 @@
+tx pull
+./tools/check-translations.sh