Append a column to a matrix : border

### 2.42.26 Append a column to a matrix : `border`

`border` takes as argument a matrix `A` of dimension p*q and a list `b` of size p (i.e. `nrows(A)=size(b)`).
`border` returns the matrix obtained by appending `tran(b)` as last column to the matrix `A`, therefore:

`border(A,b)=tran([op(tran(A)),b])=tran(append(tran(A),b))`

Input :

`border([[1,2,4],[3,4,5]],[6,7])`

Output :

`[[1,2,4,6],[3,4,5,7]]`

Input :

`border([[1,2,3,4],[4,5,6,8],[7,8,9,10]],[1,3,5])`

Output :

`[[1,2,3,4,1],[4,5,6,8,3],[7,8,9,10,5]]`