Correct spelling mistakes.

code/qcommon/unzip.c

@@ -151,7 +151,7 @@ typedef struct
 /* ===========================================================================
      Read a byte from a gz_stream; update next_in and avail_in. Return EOF
    for end of file.
-   IN assertion: the stream s has been sucessfully opened for reading.
+   IN assertion: the stream s has been successfully opened for reading.
 */
 
 
@@ -290,8 +290,8 @@ local int strcmpcasenosensitive_internal (fileName1,fileName2)
 
 /*
    Compare two filename (fileName1,fileName2).
-   If iCaseSenisivity = 1, comparision is case sensitivity (like strcmp)
-   If iCaseSenisivity = 2, comparision is not case sensitivity (like strcmpi
+   If iCaseSenisivity = 1, comparison is case sensitivity (like strcmp)
+   If iCaseSenisivity = 2, comparison is not case sensitivity (like strcmpi
                                                                 or strcasecmp)
    If iCaseSenisivity = 0, case sensitivity is defaut of your operating system
         (like 1 on Unix, 2 on Windows)