Add Gctf buildblock

No new versions were installed, but this documents the build process and
updates the modulefile.

EM/Gctf/Gctf

+#!/bin/sh
+# Wrapper for Gctf on merlin
+module purge
+module use EM
+module load cuda/8.0.44 Gctf/1.06
+exec Gctf-v1.06_sm_30_cu8.0_x86_64 "$@"

EM/Gctf/README

+# GCTF
+
+## Installation
+
+1. Download binaries from https://www2.mrc-lmb.cam.ac.uk/research/locally-developed-software/zhang-software/
+2. Update files/variants
+3. Run `./build <version>` to create directories
+4. Move all executables to /opt/psi/EM/Gctf/$VERSION/bin
+5. Create wrapper script at /opt/psi/EM/Gctf/$VERSION/bin/Gctf based on ./Gctf
+6. Fix permissions: chmod 755 /opt/psi/EM/Gctf/$VERSION/bin/*

EM/Gctf/build

+#!/usr/bin/env modbuild
+
+# Binary distribution with manual installation. See README.md
+
+pbuild::add_to_group 'EM'
+
+pbuild::prep() {
+    :
+}
+
+pbuild::configure() {
+    :
+}
+
+pbuild::compile() {
+    :
+}
+
+pbuild::install() {
+    :
+}
+

EM/Gctf/files/variants

+Gctf/0.50	stable
+Gctf/1.06	stable

EM/Gctf/modulefile

+#%Module1.0
+
+module-whatis           "Real-time CTF determination and correction"
+module-url              "https://www2.mrc-lmb.cam.ac.uk/research/locally-developed-software/zhang-software/"
+module-license          "free"
+module-maintainer       "Spencer Bliven <spencer.bliven@psi.ch>"
+
+module-help     "
+Citation: Zhang K. (2016). Gctf: Real-time CTF determination and correction. JSB, 193: 1-12.
+
+The `Gctf` script in this module includes the correct CUDA dependency. Other
+executables need CUDA loaded separately.
+"
+