Updating the readme wih `hdd_usage` details.

CHANGELOG.md

@@ -6,6 +6,10 @@ Added an option to configure the path separator. If you want something
 else than an ordinary slash, you could set
 `POWERLEVEL9K_DIR_PATH_SEPARATOR` to whatever you want.
 
+### New segment 'hdd_usage' added
+
+This segment will show the usage level of your current partition.
+
 ## v0.5.0
 
 ### `load` and `ram` changes

README.md

@@ -88,6 +88,7 @@ The segments that are currently available are:
 * [`battery`](#battery) - Current battery status.
 * [`context`](#context) - Your username and host.
 * [`dir`](#dir) - Your current working directory.
+* [`hdd_usage`](#hdd_usage) - Disk usage of your current partition.
 * `history` - The command number for the current line.
 * [`ip`](#ip) - Shows the current IP address.
 * [`public_ip`](#public_ip) - Shows your public IP address.
@@ -306,6 +307,16 @@ If you want to customize the directory separator, you could set:
 POWERLEVEL9K_DIR_PATH_SEPARATOR="%f "$'\uE0B1'" %F"
 ```
 
+##### hdd_usage
+
+The `hdd_usage` segment will show the usage level of the partition that your current working directory resides in. It can be configured with the following variables.
+
+| Variable | Default Value | Description |
+|----------|---------------|-------------|
+|POWERLEVEL9K_HDD_USAGE_ONLY_WARNING|false|Hide the segment except when usage levels have hit warning or critical levels.|
+|POWERLEVEL9K_HDD_USAGE_WARNING_LEVEL|90|The usage level that triggers a warning state.|
+|POWERLEVEL9K_HDD_USAGE_CRITICAL_LEVEL|95|The usage level that triggers a critical state.|
+
 ##### ip
 
 This segment tries to examine all currently used network interfaces and prints