fixes #1027

Problem: bootstrap.sh method archLinux() does not install wget, gperf or perl-html-parser. Documented in issue #1207 (closed)

Solution: Added three packages to be installed by pacman, the Arch package manager.

Changes introduced by this pull request:

• Put all required packages into a list such that pacman only needs to be called twice, once for general update/sync, and second time to install required packages.
• Added the --needed flag so only packages not presently installed are added. This saves needing to check for binaries, and lets the package manager handle package install checks.

Drawbacks:

• Nil seen.

TODOs:

• Nil.

Fixes:

• Issue #1207 (closed)

State:

• Ready.

Blocking/related:

• Nil.