Feature: Allow all variables to be overridden by the user

...for ULTIMATE POWER!

Previously the global variables were being set via standard:

```sh
export THIS_VAR="foo"
```

If `THIS_VAR` was set prior to the line being executed, it was overridden.  This
doesn't play well for customization.

Now we're doing this:

```sh
export THIS_VAR=${THIS_VAR:="foo"}
```

In this way, if `THIS_VAR` is set prior to this line being executed, it will
_not_ be overridden.

Because this is effectively the same thing as:

```sh
if [ -z "$THIS_VAR" ]; then
  export THIS_VAR="foo"
fi
```

I decided to go ahead and replace all the places in the code where we were doing
that check with the new `${VAR:=default}` syntax.

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Change-Id:     I67a28feea859aa24869e8a09a74c2ff1e1f24a4d
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Merge commit 'feature/allow-all-variables-to-be-overridden' into HEAD

Closes #22
Style: Quote all variable assignments

This just makes absolutely sure there's no ambiguity in how variables are set

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Change-Id:     I9b7e32c239b46cac2c7026f766d5082f6ad5f344
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: Remove the extra 'test' braces, they are redundant

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Change-Id:     I35b35b44bd8e3aedd04d7db67c7c7ce07ed48ee9
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Style: Make whitespace changes
Refactor: Make the 'for' loops simpler

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Change-Id:     Ib489fd7a13da20915fdcb0f2347294ac742aa57a
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: Add 'break' statements to shortcut the loops

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Change-Id:     I92083b3e020de7b03f655ca69ec9829642cfba25
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: All EDITOR assignments set via EDITOR_COMMAND variables

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Change-Id:     I68f290f7b73ed7267bf190c48ba721c4700a2a20
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: I don't think there's any need to check for the pagekite file

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Change-Id:     I617d92185426acad01ef866cbdabd811ab921939
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Feature: Tweak the 256 colors and add TrueColor support

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Change-Id:     I2bf5615730a5272122c451c8d0170bfbdde130b4
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Feature: Make sidekiq a bundled command

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Change-Id:     I640f027749dfb9133b6841ec72be293dcc0cd049
Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Merge commit 'feature/add-true-color-support-to-color-table' into HEAD

Closes #26
Refactor: Quote all the variable assignments that make sense to quote

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Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: Remove unnecessary complexity from for loops

No need to do this:

```sh
for foo in "${bar[@]}"; do
```

when you can do this:

```sh
for foo in $bar; do
```

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Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: Convert 'local' to 'declare' for consistency

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Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Feature: Remove unused git hook for taking photos

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Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Bugfix: Fix substitution in the Tmux pane title

The single quotes were showing in the title which is not what we wanted.

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Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>
Refactor: Remove test cases that are more specific than they need to be

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Signed-off-by: Jeff Felchner <accounts+git@thekompanee.com>