made examples/demos for vectors && files && lists | also fixed a bug with the vector and list size and popping, explained in the adjacent comment

examples/file/filedemo.c

@@ -0,0 +1,21 @@
+#include <odweta/file.h>
+#include <stdio.h>
+
+int main() {
+    printf("creating a file using 'fileInit(<filename>)' (returns a file_t*)\n");
+    file_t* f = fileInit("test.txt");
+
+    printf("printing the file contents\n\n");
+    filePrint(f);
+
+    printf("\nconvering the file contents into a string (char*)\n");
+    char* string = fileToString(f);
+    printf("\"%s\"\n", string);
+
+    // TODO -> writing, clearing
+
+    printf("if you are finished working with the file BEFORE the immediate end of the program, run 'fileCleanup(file_t*)', otherwise it is not strictly necessary\n");
+    fileCleanup(f);
+
+    return 0;
+}