fix: change section_var_file location to XDG_CACHE_HOME

Merge tag 'v4.7.0' into develop

Merge branch 'release/v4.7.0'

chore(release): 4.7.0

chore: cleanup and url fix

feat(section): changed rust emoji

feat(section): add Gradle, Maven support

Docs: flesh out explanation of custom sections

Respect ZDOTDIR env var when looking for .zshrc

fix: Hardened the Docker context checking logic

chore: cleanup travis, gitbook config files

chore: spaceship -> spacezsh

doc: update changelog and tweak readme

fix(vi-mode): drop hack solution for vi mode conflict

Merge tag 'v4.6.0' into develop