Add a script to create env variables and travis folding helpers

Implement travis folding helpers

Add a script to create env variables and travis folding helpers

Implement travis folding helpers

Source all of the shell scripts

Remove  since we are sourcing

Fix syntax of travis fold commands

Put the travis folds in the individual files

Put the min test and flake in their own files

Reinstate top level venv activation

Remove unused script commands

Fix travis_fold syntax
Switch to a single script to get the folds to work

Switch to a single script to get the folds to work

Replace the old install_min with this before_install script

Reinstate optional installs and add headers

move the display setup to the travis_script

Use force remove on temp directory

Always retry on pip

Fix the travis_retry pip alias

Source the before_install script and move the alias

Create bash functions for folding and export DISPLAY

Export fold functions

Make repip a function
Use our own retry command since travis_retry is not exported

Use our own retry command since travis_retry is not exported

Reinstate the MPL settings

Fix the order of the MPL settings

Fix the MPL versions

Streamline the section headers

Adjust min MPL requirement for the Ubuntu version

Force pip to not install matplotlib and scipy
Use the system python for 2.7
Do not explicitly remove packages from requirements.txt
Fix usage of set command

Fix usage of set command

Fix set command again

Fix mpl directory for python 2.7
Fix section titles to avoid spaces
Add a coveralls repo token
Update travis_notes and move to tools folder
Merge pull request #1293 from blink1073/streamline-travis

Streamline Travis-CI build