Moves creating the emoji folder from the provisioning script to
the build_emoji script.
Fixes the fact that the emoji cache directory wasn't being created
when not using the provision.py script.
Modified composebox_typeahead.js to recognize the triple backtick
and tilde for code blocks, and added appropriate typeahead functions
in that file and in typeahead_helper.js.
Additionally, a new file pygments_data.js contains a dictionary of
the supported languages, mapping to relative popularity
rankings. These rankings determine the order of sort of the
languages in the typeahead.
This JavaScript file is actually in static/generated/pygments_data.js, as it
is generated by a Python script, tools/build_pymgents_data.py. This is
so that if Pygments adds support for new languages, the JavaScript file
will be updated appropriately. This python script uses a set of popularity
rankings defined in lang.json.
Corresponding unit tests were also added.
Fixes#4111.
Before this commit, provisioning was done by executing provision.py,
which printed the log directly to stdout, making debugging harder.
This commit creates a wrapper bash script 'provision' in tools, which
calls 'zulip/scripts/tools/provision_vm.py' (the new location of
provision.py) and prints all the output to
'zulip/var/log/zulip/zulip_provision.log' via 'tee'.
Travis tests and docs have been modified accordingly.