Corrected ScriptExecution and added tests

gclc/src/test/resources/script2.txt

@@ -0,0 +1 @@
+# test only comment

gclc/src/test/resources/script3.txt

@@ -0,0 +1 @@
+test

gclc/src/test/resources/script4.txt

@@ -0,0 +1,5 @@
+# Test file with commands
+test
+# and comments
+long
+# interwined

gclc/src/test/resources/script5.txt

@@ -0,0 +1,2 @@
+# A script with arguments
+{0}