add support for faasd

[nitishkumar71]

Description

Add support for faasd get
https://github.com/openfaas/faasd

Motivation and Context

• I have raised an issue to propose this change, which has been given a label of design/approved by a maintainer (required)
  Closes support faasd installation #1051

How Has This Been Tested?

If updating or adding a new CLI to arkade get, run:

go build && ./hack/test-tool.sh TOOL_NAME

running above instructions produced below output

+ ./arkade get faasd --arch arm64 --os darwin --quiet
+ file /home/nitishkumar/.arkade/bin/faasd
/home/nitishkumar/.arkade/bin/faasd: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), statically linked, Go BuildID=r1HivDWZUWTY06krAYzh/jr0ngqiOkScj5PurSkGt/il-__0YOtoWkGaYktW3F/_q1Q2cmdX43gKbps8PYU, stripped
+ rm /home/nitishkumar/.arkade/bin/faasd
+ echo

+ ./arkade get faasd --arch x86_64 --os darwin --quiet
+ file /home/nitishkumar/.arkade/bin/faasd
/home/nitishkumar/.arkade/bin/faasd: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, Go BuildID=UnUzsITfwYSOoP4MS0Ph/rcplXRzmJiIITNp5W_2k/eJoXKxxhjtnSu4y1BsCV/QvVb1zzgGDkn0yyUemLQ, stripped
+ rm /home/nitishkumar/.arkade/bin/faasd
+ echo

+ ./arkade get faasd --arch x86_64 --os linux --quiet
+ file /home/nitishkumar/.arkade/bin/faasd
/home/nitishkumar/.arkade/bin/faasd: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, Go BuildID=UnUzsITfwYSOoP4MS0Ph/rcplXRzmJiIITNp5W_2k/eJoXKxxhjtnSu4y1BsCV/QvVb1zzgGDkn0yyUemLQ, stripped
+ rm /home/nitishkumar/.arkade/bin/faasd
+ echo

+ ./arkade get faasd --arch aarch64 --os linux --quiet
+ file /home/nitishkumar/.arkade/bin/faasd
/home/nitishkumar/.arkade/bin/faasd: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), statically linked, Go BuildID=r1HivDWZUWTY06krAYzh/jr0ngqiOkScj5PurSkGt/il-__0YOtoWkGaYktW3F/_q1Q2cmdX43gKbps8PYU, stripped
+ rm /home/nitishkumar/.arkade/bin/faasd
+ echo

+ ./arkade get faasd --arch x86_64 --os mingw --quiet
+ file /home/nitishkumar/.arkade/bin/faasd.exe
/home/nitishkumar/.arkade/bin/faasd.exe: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), statically linked, Go BuildID=UnUzsITfwYSOoP4MS0Ph/rcplXRzmJiIITNp5W_2k/eJoXKxxhjtnSu4y1BsCV/QvVb1zzgGDkn0yyUemLQ, stripped
+ rm /home/nitishkumar/.arkade/bin/faasd.exe
+ echo

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Documentation

• I have updated the list of tools in README.md if (required) with ./arkade get --format markdown
• I have updated the list of apps in README.md if (required) with ./arkade install --help

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I've read the CONTRIBUTION guide
• I have signed-off my commits with git commit -s

• I have tested this on arm, or have added code to prevent deployment

[alexellis]

Approved