📚 Add installation instructions to README (#5)

Add installation instructions to README

README.md

@@ -16,6 +16,16 @@ Please be careful. You can get your Authy account suspended very easily by using
 ### authy-export
 This program will enrol itself as an additional device on your Authy account and export all of your TOTP tokens in [Key URI Format](https://github.com/google/google-authenticator/wiki/Key-Uri-Format).
 
+**Installation**
+
+Pre-built binaries are available from the [releases page](https://github.com/alexzorin/authy/releases).
+
+Alternatively, it can be compiled from source, which requires [Go 1.12 or newer](https://golang.org/doc/install):
+
+```shell
+go get github.com/alexzorin/authy/cmd/authy-export
+```
+
 **To use it:**
 
 1. Run `authy-export`
@@ -50,4 +60,4 @@ The above copyright notice and this permission notice shall be included in all c
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-All product names, logos, and brands are property of their respective owners. All company, product and service names used in this website are for identification purposes only. Use of these names, logos, and brands does not imply endorsement
+All product names, logos, and brands are property of their respective owners. All company, product and service names used in this website are for identification purposes only. Use of these names, logos, and brands does not imply endorsement