Update minimum git version to v1.17.10

Per nvm-sh#1704 (comment)

README.md

@@ -119,11 +119,11 @@ Homebrew installation is not supported. If you have issues with homebrew-install
 
 **Note:** If you're using `zsh` you can easily install `nvm` as a zsh plugin. Install [`zsh-nvm`](https://github.com/lukechilds/zsh-nvm) and run `nvm upgrade` to upgrade.
 
-**Note:** Git versions before v1.7 may face a problem of cloning nvm source from GitHub via https protocol, and there is also different behavior of git before v1.6, so the minimum required git version is v1.7.0 and we recommend v1.7.9.5 as it's the default version of the widely used Ubuntu 12.04 LTS. If you are interested in the problem we mentioned here, please refer to GitHub's [HTTPS cloning errors](https://help.github.com/articles/https-cloning-errors/) article.
+**Note:** Git versions before v1.7 may face a problem of cloning nvm source from GitHub via https protocol, and there is also different behavior of git before v1.6, and git prior to [v1.17.10](https://github.com/git/git/commit/5a7d5b683f869d3e3884a89775241afa515da9e7) can not clone tags, so the minimum required git version is v1.7.10. If you are interested in the problem we mentioned here, please refer to GitHub's [HTTPS cloning errors](https://help.github.com/articles/https-cloning-errors/) article.
 
 ### Git install
 
-If you have `git` installed (requires git v1.7+):
+If you have `git` installed (requires git v1.7.10+):
 
 1. clone this repo in the root of your user profile
   - `cd ~/` from anywhere then `git clone https://github.com/creationix/nvm.git .nvm`
@@ -161,7 +161,7 @@ export NVM_DIR="$HOME/.nvm"
 
 ### Manual upgrade
 
-For manual upgrade with `git` (requires git v1.7+):
+For manual upgrade with `git` (requires git v1.7.10+):
 
 1. change to the `$NVM_DIR`
 1. pull down the latest changes