Updated install instructions for Ubutu 12.04 server about thingspeak

Thank you very much.

The maintainer of this repo should really update the tutorial.
I was very confused about ruby-2.1.0 is not installed.
Now my wandboard is compiling ruby from sources again for hours....
(I dont need your script for source compiling, if i do rvm install ruby-2.1.0, rvm do that for me.

Sorry for my English

Addition: I had to do
$ gem install rails --version=4.0.0.rc1 # to get bundle and rails 4

[billzhonggz]

I have found a similar problem on Ubuntu 16.04LTS. Since the project requires exactly ruby-2.1.0 and OS pre-installed ruby-2.3.0, so before installing the bunlder, it should be switched to the ruby-2.1.0 by rvm.

I really forgot about this problem. Id not touched thingspeak since 2015. 3 years ago... Now i would prefer using a docker container with the complete environment inside. There are many available.

https://hub.docker.com/r/greyltc/thingspeak/~/dockerfile/
(Id not tested the container, its just for reference that there's something easier to use than installing it your own, use at your own risk)