Recommended documentation updates.

[jordanmack]

https://github.com/nervosnetwork/capsule/wiki/Installing-Capsule#build-and-install-capsule

Update the install command to use the develop branch.

cargo install ckb-capsule --git https://github.com/nervosnetwork/capsule.git --branch develop

---

Adding some of the common errors with installing via Cargo would be beneficial to add to the Wiki. This will allow it to be picked up by search engines so it can be located by users experiencing the problem in the future. This could be added to the bottom of the current "Installing Capsule" wiki page, or a new page.

Error:

error: linker `cc` not found`

Solution: Install common build tools for your OS.
Debian/Ubuntu: sudo apt install -y build-essential
OpenSUSE: sudo zypper install -t pattern devel_basis
MacOS: Xcode Command Line Tools https://developer.apple.com/library/archive/technotes/tn2339/

Error:

run pkg_config fail: Could not run `PKG_CONFIG_ALLOW_SYSTEM_CFLAGS="1" "pkg-config" "--libs" "--cflags" "openssl"`
The pkg-config command could not be found.`

Solution: Install pkg-config.
Debian/Ubuntu: sudo apt install -y pkg-config

Error:

run pkg_config fail: `PKG_CONFIG_ALLOW_SYSTEM_CFLAGS="1" "pkg-config" "--libs" "--cflags" "openssl"` did not exit successfully: exit status: 1
error: could not find system library 'openssl' required by the 'openssl-sys' crate

Solution: Install the OpenSSL Development Toolkit.
Debian/Ubuntu: sudo apt install -y libssl-dev
CentOS / Fedora: sudo yum install openssl-devel
OpenSUSE: sudo zypper install libopenssl-devel

Error:

error: failed to run custom build command for `ckb-capsule v0.10.2 (/root/.cargo/git/checkouts/capsule-456f646e9dda89ac/366e6ee)`
thread 'main' panicked at build.rs:27:17:
error when get commit id: `git` was not found!

Solution: Install Git.
Debian/Ubuntu: sudo apt install -y git