Update limitbalance.rst

Fixed typo

docs/source/limitbalance.rst

@@ -5,8 +5,8 @@ Base contract that provides mechanism for limiting the amount of funds a contrac
 
 LimitBalance(unit _limit)
 """"""""""""""""""""""""""""
-Constructor takes an unisgned integer and sets it as the limit of funds this contract can hold.
+Constructor takes an unsigned integer and sets it as the limit of funds this contract can hold.
 
 modifier limitedPayable()
 """"""""""""""""""""""""""""
-Throws an error if this contract's balance is already above the limit.
+Throws an error if this contract's balance is already above the limit.