fixed a few typos

Author: mahrud

M2/Macaulay2/packages/NumericalSemigroups.m2

@@ -461,7 +461,7 @@ apery List := HashTable => L -> (
     a := 0; -- number of keys already filled in A
     S := set L + set{0}; -- S will hold all the semigroup elmeents found, including 0
 
-    --now look for new Apery set elememts and semigroup elements until
+    --now look for new Apery set elements and semigroup elements until
     --all the keys have been filled.
     s := m;
     while a < m-1 do(
@@ -2797,7 +2797,7 @@ Inputs
  g:ZZ
   genus
  m:ZZ
-  mutiplicity
+  multiplicity
  c:ZZ
   conductor
 Outputs

M2/Macaulay2/packages/PencilsOfQuadrics.m2

@@ -2805,7 +2805,7 @@ doc ///
     Text
      A vector bundle on a hyperelliptic curve E with
      equation y^2 - (-1)^g * f
-     can be represeted by it's pushforward V to PP^1,
+     can be represented by it's pushforward V to PP^1,
      under the degree 2 map, 
      which will be a vector bundle of twice the rank,
      together with a matrix 

M2/Macaulay2/packages/Permutations/docs.m2

@@ -972,7 +972,7 @@ doc ///
     extend
     (extend, Permutation, ZZ)
   Headline
-    rewrites a permutation as a permution on more symbols
+    rewrites a permutation as a permutation on more symbols
   Usage
     extend(w,n)
   Inputs