git-gui: correct spelling errors in comments

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>
diff --git a/lib/spellcheck.tcl b/lib/spellcheck.tcl
index e612030..538d61c 100644
--- a/lib/spellcheck.tcl
+++ b/lib/spellcheck.tcl
@@ -14,7 +14,7 @@
 field s_menuidx 0 ; # last index of insertion into $w_menu
 
 field s_i           {} ; # timer registration for _run callbacks
-field s_clear        0 ; # did we erase mispelled tags yet?
+field s_clear        0 ; # did we erase misspelled tags yet?
 field s_seen    [list] ; # lines last seen from $w_text in _run
 field s_checked [list] ; # lines already checked
 field s_pending [list] ; # [$line $data] sent to ispell/aspell
@@ -259,7 +259,7 @@
 		if {$n == $cur_line
 		 && ![regexp {^\W$} [$w_text get $cur_pos insert]]} {
 
-			# If the current word is mispelled remove the tag
+			# If the current word is misspelled remove the tag
 			# but force a spellcheck later.
 			#
 			set tags [$w_text tag names $cur_pos]