added ocaml and opam

see_also/ocaml

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+ocaml
+opam

see_also/opam

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+ocaml
+opam

sheets/opam

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+# OPAM is a source-based package manager for OCaml
+
+# Initialize ~/.opam using an already installed OCaml
+opam init
+opam init --comp 4.02.3
+# Initialize with a freshly compiled OCaml 4.02.3
+
+# List all available packages
+opam list -a
+
+# List packages with QUERY in their name or description
+opam search ${QUERY}
+
+# Display information about PACKAGE
+opam show ${PACKAGE}
+
+# Download, build and install the latest version of PACKAGE
+# and all its dependencies
+opam install ${PACKAGE}
+
+# Update the packages database
+opam update
+
+# Bring everything to the latest version possible
+opam upgrade
+
+# Command-specific manpage
+opam CMD --help
+
+# install static analysis and indentation for ocaml
+opam install ocp-indent merlin
+# configure editor as recommended in the installation output
+# + (for vim) don't forget to add "filetype plugin on" in ~/.vimrc
+