Implement more ocaml options

[andrewray]

The following are potential candidates (esp. -short-paths).

Usage: ocaml <options> <object-files> [script-file [arguments]]
options are:
  -absname  Show absolute filenames in error messages
  -I <dir>  Add <dir> to the list of include directories
  -labels  Use commuting label mode
  -no-app-funct  Deactivate applicative functors
  -noassert  Do not compile assertion checks
  -nolabels  Ignore non-optional labels in types
  -nostdlib  Do not add default directory to the list of include directories
  -principal  Check principality of type inference
  -rectypes  Allow arbitrary recursive types
  -short-paths  Shorten paths in types
  -strict-sequence  Left-hand part of a sequence must have type unit
  -w <list>  Enable or disable warnings according to <list>:
        +<spec>   enable warnings in <spec>
        -<spec>   disable warnings in <spec>
        @<spec>   enable warnings in <spec> and treat them as errors
     <spec> can be:
        <num>             a single warning number
        <num1>..<num2>    a range of consecutive warning numbers
        <letter>          a predefined set
     default setting is "+a-4-6-7-9-27-29-32..39-41..42-44-45"
  -warn-error <list>  Enable or disable error status for warnings according
     to <list>.  See option -w for the syntax of <list>.
     Default setting is "-a"