fix typos

[spaette]

dumped repo strings exposed two typos

[lcw]

Thanks!

[spaette]

cf: #850

@lcw caught a couple more typos

$ grep -nr Intialized MPI.jl
MPI.jl/src/environment.jl:290:$(_doc_external("MPI_Intialized"))
$ grep -nr analagous MPI.jl
MPI.jl/src/collective.jl:785:Inclusive prefix reduction (analagous to `accumulate` in Julia): `recvbuf` on rank `i`
MPI.jl/src/collective.jl:816:Inclusive prefix reduction (analagous to `accumulate` in Julia): `recvbuf` on rank `i`
MPI.jl/src/collective.jl:840:Exclusive prefix reduction (analagous to `accumulate` in Julia): `recvbuf` on rank `i`
MPI.jl/src/collective.jl:872:Exclusive prefix reduction (analagous to `accumulate` in Julia): `recvbuf` on rank `i`
$ 

[giordano]

#850