Use jemalloc for Ruby 2.2 and 2.4 (#2535)

[ci fw-only Ruby/sinatra Ruby/sinatra-sequel Ruby/rails Ruby/grape]

toolset/setup/linux/languages/ruby/ruby-2.2.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-fw_depends llvm-dev rvm
+fw_depends llvm-dev libjemalloc-dev rvm
 
 fw_installed ruby-2.2 && return 0
 
@@ -8,7 +8,7 @@ fw_installed ruby-2.2 && return 0
 # update this when it changes
 MRI_VERSION=2.2.6
 
-rvm install $MRI_VERSION
+rvm install $MRI_VERSION -C --with-jemalloc
 
 rvm $MRI_VERSION do gem install bundler -v 1.14.3
 

toolset/setup/linux/languages/ruby/ruby-2.4.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-fw_depends llvm-dev rvm
+fw_depends llvm-dev libjemalloc-dev rvm
 
 fw_installed ruby-2.4 && return 0
 
@@ -8,7 +8,7 @@ fw_installed ruby-2.4 && return 0
 # update this when it changes
 MRI_VERSION=2.4.0
 
-rvm install $MRI_VERSION
+rvm install $MRI_VERSION -C --with-jemalloc
 
 rvm $MRI_VERSION do gem install bundler -v 1.14.3