Merge pull request #29 from orzrd/master

Add new installation method for pypi/ubuntu/gentoo and hotfix a python3 install error
Separate g++ log with blue section lines

Every time g++ use "in/at", it starts a new error/warning paragraph.
Coloring those lines in blue mades it easier to spot messages.
json separators in yellow, color double quotes
Expect formatted json as input, blue numbers

This patch avoid coloring what's inside item's strings, but expect a formatted input.
Use python3's importlib instead of __import__
Color code after a "note: candidate is/are:"
Forgot to remove a test print
Refactoring: move stdin/out up to __main__

Use explicit stream variable in inner functions,
sys streams are thus only in use in the upper layer.
Add GIMP palettes support, refactoring

You can now use GIMP palette file as a colormap, by using its filename as a color.
Add the well known Matlab jet72 palette (jet72.gpl).

Group functions in sections.
Compress colormaps converted from RGB to ANSI

Avoid having two duplicated consecutives colors when using colormaps.
Feature #31: better error handling

Add dedicated exception and exit on specific error code.
Also put resource loading in separated functions.
feature #32: debug mode
Add an option to print all the available features
feature #33: handle resources dirs. bugfix duplicated themes

Add -T and -P options to search for themes/palettes in additional directories.
Raise an error if duplicated themes name are found.
bugfix: cleanly handle more errors when loading resources

Also print lexers after palettes.
bugfix: parse the scale min/max as float, not int
Update the README with recent features
Support for RGB hexadecimal triplets colors notations
bugfix: correct ANSI colors range in rgb_to_ansi

The function was trying to convert colors with values greater than 234, which do not exists in ANSI.
Refactoring colormaps

Bugfix scale configuration and logging.
Move every color map in colormaps
Use the case convention to switch mode.
Add a 256-colors mode scale (feature #37).
Add the spectrums colormaps, use them for scales by default.
Log the complete ANSI palettes numbers.