Merge pull request #247 from LiskHQ/225-nvm_fail

Fix nvm failure in toolchain/installLinux.sh - Closes #225

toolchains/install_linux.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
-# 
+#
 # LiskHQ/lisk-build
 # Copyright (C) 2017 Lisk Foundation
 #
@@ -32,5 +32,8 @@ CMDS=("apt-get" "curl" "sudo")
 check_cmds CMDS[@]
 
 exec_cmd "curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.0/install.sh | bash"
-exec_cmd "nvm install v6.12.2"
+export NVM_DIR="/home/$USER/.nvm"
+# shellcheck source=/dev/null
+[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" # This loads nvm
+nvm install v6.12.2
 exec_cmd "sudo apt-get install -y autoconf automake build-essential curl chrpath git libreadline6-dev libtool zlib1g-dev libssl-dev libpq-dev nodejs python wget libncurses5-dev"